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Anna Strambo Pamela Linwood Gerard Dorrity CHARGE English for Electronics and Telecommunications with Computer Overview TECHNICAL DICTIONARY CON LETTURE DI APPROFONDIMENTO PER L’INDIRIZZO ELETTRONICA E TELECOMUNICAZIONI

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Anna StramboPamela Linwood Gerard Dorrity

ISBN 978-88-494-1274-1

Strambo Linwood Dorrity

On Charge - Elettronica

PETRINI

Questo volume, sprovvisto del talloncino a lato, è da conside-rarsi copia di SAGGIO-CAMPIONE GRATUITO, fuori commercio(vendita e altri atti di disposizione vietati: art. 17, c. 2, L.633/1941). Fuori campo applicazione I.V.A. (D.P.R. 26/10/72, n. 633, art. 2,3° co, lett. d.)

www.scuola.com

A. Stram

bo P. Linwood G. Dorrity

CHARGEEnglish for Electronics and Telecommunications

with Computer Overview

ON

CH

AR

GE

ELETTRO

NICA

E TELECOM

UN

ICAZIO

NI

TECHNICAL DICTIONARY

On Charge si rivolge agli studenti del triennio degliIstituti Tecnici Industriali e degli Istituti Professionali conspecializzazione in Elettronica e Telecomunicazioni edElettrotecnica e Automazione. È proposto in due versioni differenti che presentanouna sezione di Reading Supplements, letture diapprofondimento diverse a seconda degli indirizzi.

Il corso si articola in unità didattiche, disposte in 4 sezioni disciplinari (Electricity, Electronics,Computer Overview, Telecommunications). Ogni unità propone due letture corredate di attivitàe si articola in rubriche ricorrenti: • Getting started introduzione dei concetti e dei vocaboli principali• Focus on content una prima lettura di carattere più generale con attività di comprensione• Focus on skills una seconda lettura più specifica con attività focalizzate sulle abilità• Grammar extension revisione delle strutture grammaticali con esercizi di controllo• Check your progress esercizi di tipo sommativo per valutare il raggiungimento degli obiettivi.

Le pagine finali presentano le sezioni di Job skills e di Study skills, Grammar Section eGlossary.

On Charge si compone di:• Student’s Book + CD-Rom• 3 cd audio/Rom per la classe – contenenti le registrazioni

dei testi-base e delle attività di Listening. • Teacher’s Book

Allegato al testo un minidizionario di inglese tecnicosu cd-rom con lemmi speakerati da un madrelingua.

CHARGE

On Charge + CD Rom (indivisibili)

Prezzo di vendita al pubblico € 19,00(Defiscalizzato € 18,27)

CON LETTUREDI APPROFONDIMENTOPER L’INDIRIZZO

ELETTRONICAE TELECOMUNICAZIONI

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Anna StramboPamela Linwood Gerard Dorrity

CHARGEEnglish for Electronics and Telecommunications

with Computer Overview

CON LETTUREDI APPROFONDIMENTO

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internet: www.petrini.it

e-mail: [email protected]

Le fotografie di copertina sono state fornite da:George Diebold Photography, Gettyimages; Satellite communication Antenna, ConstructionPhotography/Corbis; Shanghai Maglev Train Station, Xiaoyang Liu/Corbis; Robotic Handshake,William Whitehurst/Corbis

Le fotografie di questo volume sono state fornite da: DeA Picture Library; Lucidio Studio Inc./Corbis; P. Souders/Corbis; Bettmann/Corbis; M. Monetti;T. Kitamura/AFP/Grazia Neri; A. Cooper/Corbis; Creasource/Corbis; G. Schuster/Zefa/Corbis; J.Ayissi/AFP/Grazia Neri; DeA Picture Library/A. De Gregorio; H. Gal/Corbis; SchenectadyMuseum, Hall of Electrical History Foundation/Corbis; W. Whitehurst/Corbis; Ch.Doyle/Photonica/Getty Images/L. Ronchi; L. Williams/Zefa/Corbis; S. Stulberg/Corbis; DeAPicture Library/Photo 1; R.H. Wetmore II/Stone/Getty Images/L. Ronchi; R. Ressmeyer/Corbis;Reuters/Contrasto; R. Chapple/Taxi/Getty Images/L. Ronchi; Y. Arthus-Bertrand/Corbis; VisualsUnlimited/Corbis; DeA Picture Library/Getty Images/L. Ronchi; M.S. Yamashita/Corbis; A.Francekevich/Photographer’s Choice/Getty Images/L. Ronchi; V. Lombardo/Photographer’sChoice/Getty Images/L. Ronchi; K. Kittle/Corbis; W. McNamee/Corbis; Yogi, Inc./Corbis

Edizione: I II III IV V VI

Anno: 2008 2009 2010 2011 2012 2013

Stampa: AGF - Italia – Peschiera Borromeo (MI)

Proprietà letteraria riservata© 2008 De Agostini Scuola SpA – Novara1ª edizione: gennaio 2008Printed in Italy

L’Editore dichiara la propria disponibilità a regolarizzare eventuali omissioni o errori di attribuzione.Nel rispetto del DL 74/92 sulla trasparenza nella pubblicità, le immagini escludono ogni e qualsiasi possi-bile intenzione o effetto promozionale verso i lettori.

Tutti i diritti riservati. Nessuna parte del materiale protetto da questo copyright potrà essere riprodotta inalcuna forma senza l’autorizzazione scritta dell’Editore.

Fotocopie per uso personale del lettore possono essere effettuate nei limiti del 15% di ciascunvolume/fascicolo di periodico dietro pagamento alla SIAE del compenso previsto dall’art. 68, comma 4,della legge 22 aprile 1941 n.633.Le riproduzioni ad uso differente da quello personale potranno avvenire, per un numero di pagine nonsuperiore al 15% del presente volume/fascicolo, solo a seguito di specifica autorizzazione rilasciata daAIDRO – Corso di Porta Romana, 108 – 20122 Milano – e-mail [email protected] e sito [email protected];www.aidro.orgEventuali segnalazioni di errori o refusi e richieste di chiarimenti sulle scelte operate dagli autori e dallaCasa Editrice possono essere inviate all’indirizzo di posta elettronica della redazione.

Coordinamento editoriale: Anna Moretta

Si ringraziano i professori G. Carnevale Carlino, P. Citarda, G. Korwin, R. Magnaguagno, S.Ovazza, P. Pezzali, A. Scarpari, R. Sempio, B. Varotto, L. Vettore per gli utili suggerimenti.

L’editore ha controllato fino alla fase di prestampa del corso che i siti internet citati avesserocontenuti compatibili con le finalità educative del testo.

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III

On Charge è un corso di inglese per il triennio degli Istituti TecniciIndustriali e per gli Istituti Professionali con specializzazione inElettrotecnica, Elettronica e Telecomunicazioni. È disponibile in due ver-sioni – blu e rossa – con letture di approfondimento diverse per i due indi-rizzi. Il corso è rivolto a studenti che abbiano una conoscenza generale dellagrammatica e del lessico di base inglesi. Tale livello di conoscenza corri-sponde di norma all’inizio del triennio di studi superiori. Grazie all’utiliz-zo di materiali aggiornati e stimolanti e alla presenza di attività diversifi-cate, On Charge si propone di aiutare gli studenti a raggiungere una padro-nanza operativa del linguaggio tecnico e, nello stesso tempo, a rafforzarele abilità di comprensione scritta e orale acquisite negli anni precedenti.

Lo Student’s Book è articolato in 4 sezioni – Electricity, Electronics,Computer Overview, Telecommunications – ognuna delle quali è costitui-ta da un numero variabile di unità, per un totale di 24. Si è cercato diseguire un criterio progressivo per quanto riguarda la complessità dellestrutture linguistiche e del lessico, mentre per quanto riguarda gli argo-menti, le unità sono indipendenti e permettono una trattazione flessibilea seconda delle necessità della classe o di eventuali percorsi pluridiscipli-nari. Le unità sono strutturate nel modo seguente:

• Getting Started – attività e/o brevi testi introduttivi tramite i quali glistudenti possono mostrare le loro conoscenze tecniche pregresse e/o leloro capacità di intuizione e anticipazione rispetto ai contenuti del-l’unità.

• Focus on Content – testi base di contenuto tecnico che stimolano l’ap-prendimento della grammatica e del lessico specifico attraverso la pre-sentazione di argomenti già noti agli studenti nella loro lingua madre.

• Focus on Vocabulary – attività ed esercizi di potenziamento linguisticoche fanno riferimento al testo del Focus on Content e ai testi eventual-mente presenti nel Getting Started.

• Focus on Skills – testi di varia tipologia e provenienza a carattere piùdivulgativo e presentati in forma di letture e di ascolti. Il loro scopo èstimolare l’utilizzo autonomo delle strutture e del lessico appresi e/opotenziati attraverso attività di produzione orale e scritta.

• Grammar Extension – tabelle grammaticali e/o brevi spiegazioni rela-tive a strutture presenti nei testi dell’unità e accompagnate da esercizi.I rimandi alla Grammar Section che si trova a fondo libro, fornisconoagli studenti integrazioni e esercizi supplementari.

• Check your progress – rubrica di chiusura dell’unità che permette aglistudenti, tramite attività di tipologia varia, una prima autovalutazionedi quanto appreso dal punto di vista grammaticale, lessicale e contenu-tistico.

Presentazione

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IV

PRESENTAZIONE

Al termine delle 24 unità vengono introdotte 15 schede incentrate sulleabilità essenziali in campo professionale (job skills) e nello studio (studyskills).

Parte integrante e assoluto punto di forza del testo sono i ReadingSupplements, presenti in due versioni diverse per l’indirizzo elettrotecni-co e per l’indirizzo elettronico e delle telecomunicazioni. Si tratta di 23 let-ture per ciascun indirizzo, corredate da esercizi di comprensione e di lessi-co, che si configurano come materiale extra da utilizzare in classe o a casa:loro caratteristica fondamentale è la trattazione di argomenti di estremaattualità che approfondiscono temi collegati al testo.

On Charge è completato da una Grammar Section, con agili notegrammaticali che affiancano e integrano le Grammar Extensions delleunità e una serie di esercizi utili per lavori di revisione e recupero, e da unGlossary finale che raccoglie i vocaboli tecnici più significativi delle unitàfornendone una breve spiegazione in lingua e il traducente italiano.

Data la grande importanza della corretta pronuncia di sigle e terminispecialistici, talvolta difficilmente reperibili sui dizionari ma fondamentaliper una efficace comunicazione fra tecnici nel mondo del lavoro, OnCharge mette a disposizione un dizionario tecnico su cd-rom con i lemmispeakerati e tre cd audio per la classe su cui sono registrate non solo leattività di listening propriamente dette, ma anche i testi tecnici dellasezione Focus on Content di ogni unità: gli studenti avranno così l’oppor-tunità di ascoltare testi letti da differenti voci madrelingua.Per i docenti è disponibile il Teacher’s Book, che contiene le soluzioni degliesercizi con alcuni suggerimenti operativi e i tapescripts delle attività dilistening, 24 tests di valutazione fotocopiabili – uno per unità – (disponi-bili anche in versione word sul primo dei cd audio classe, per una piùautonoma gestione da parte dei docenti), 10 schede per simulazioni dellaTerza Prova d’esame e alcuni “projects” tecnico-pratici di varia difficoltàda svolgere singolarmente o a gruppi e da presentare in lingua inglese difronte alla classe.

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V

UNIT 1 Basic electricity (1)• The atom and current electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4• Atomic and sub-atomic particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

UNIT 2 Basic electricity (2)• Electric charges and static electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12• How photocopiers work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

UNIT 3 Materials and their electrical properties• Conductors, insulators, semiconductors and superconductors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20• Superconductors – the key to energy efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

UNIT 4 Magnetism and Electromagnetism• The principles of magnetism and electromagnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28• Maglev vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

UNIT 5 Measuring electricity • Electrical measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36• Understanding Units of Measure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

UNIT 6 Current and circuits• DC and AC circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44• Danger! Electric shock! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

UNIT 7 AC and DC generators• The generation of current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52• Energy production – which way forward? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

UNIT 8 Electric motors• Types and features of DC and AC motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60• Robotics and automation (1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

UNIT 9 Batteries• Types of battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68• Fuel Cells: The Clean Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Grammar Extension: The passive (3)

Grammar Extension: Present tenses in time and conditions clauses

Grammar Extension: The passive (2)

Grammar Extension: Noun strings

Grammar Extension: Relative pronouns (1)

Grammar Extension: Verb patterns (1)

Grammar Extension: Comparative and superlatives

Grammar Extension: The passive (1)

Grammar Extension: Logical connectors

Table of contents

SECTION 1 ELECTRICITY

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Table of contents

VI

UNIT 10 Basic electronics• Passive components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76• Curious facts about Vacuum Tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

UNIT 11 Transistors• The 20th century’s most important invention? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84• The Birthplace of the Transistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

UNIT 12 Logic gates• Digital logic systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92• Intel – company history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

UNIT 13 Ics – Integrated circuits• Microchips and their characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100• Robotics and automation (2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

UNIT 14 Microprocessors• What is a microprocessor? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108• Nanotechnology: dream or reality? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113Grammar Extension: Verb patterns (2)

Grammar Extension: Special comparative forms

Grammar Extension: The Simple past

Grammar Extension: Quantifiers

Grammar Extension: Defining and non-defining relative clauses

UNIT 15 Basic IT (1)• Computer systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116• Robotics and automation (3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

UNIT 16 Basic IT (2)• Computer languages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124• Virtual Worlds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

UNIT 17 Networks• How networks communicate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132• Social networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

UNIT 18 The Internet • Web browsers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140• How much does the Internet weigh? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145Grammar Extension: Special passive forms

Grammar Extension: Verb patterns (3)

Grammar Extension: Opposites

Grammar Extension: Uncountable nouns

SECTION 2 ELECTRONICS

SECTION 3 COMPUTER OVERVIEW

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VII

UNIT 19 Communications modes (1)• Transmission lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148• Wireless communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

UNIT 20 Communications modes (2)• Features and applications of optical fibres . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156• Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

UNIT 21 Radio and television communications• From transmitter to TV screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164• Plasma vs liquid crystals: know the facts before you buy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

UNIT 22 Telephones, faxes and modems • How telephones work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172• Fax machines and modems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

UNIT 23 Antennas • What antenna do . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180• Types of antennas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

UNIT 24 Artificial satellites and satellite communications • Types of artificial satellites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188• Communication architectures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193Grammar Extension: Using impersonal language

Grammar Extension: Articles

Grammar Extension: Using modals

Grammar Extension: Conditional sentences

Grammar Extension: to + base form; for + ing form

Grammar Extension: Present perfect vs Simple past

READING SUPPLEMENTS 211-233

JOB SKILLS/STUDY SKILLS 194-209

Letters requesting information . . . . . . . . . . . . . . . 194Letters confirming orders . . . . . . . . . . . . . . . . . . . . 195Letters of complaint and apology . . . . . . . . . . . . . 196Telephoning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197Writing a report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198Describing companies . . . . . . . . . . . . . . . . . . . . . . . 199Describing charts (1) . . . . . . . . . . . . . . . . . . . . . . . . 200Describing charts (2) . . . . . . . . . . . . . . . . . . . . . . . . 201

Reading job ads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202Writing a curriculum and a letter of application . 203Managing job interviews . . . . . . . . . . . . . . . . . . . . . 204Internet English . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205Reading mathematical symbols . . . . . . . . . . . . . . 206Checking the pronunciation of words . . . . . . . . . 207Using a dictionary (1) . . . . . . . . . . . . . . . . . . . . . . . . 208Using a dictionary (2) . . . . . . . . . . . . . . . . . . . . . . . . 209

Grammar Section . . . . . . . . . . . . . . . . . . . . . . . . 235-253 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254-258

SECTION 4 TELECOMMUNICATIONS

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Two atoms bump into each other.

A neutron walks into a bar and asks the barman:

2

Basic Electricity (1)1UNIT SECTION 1 ELECTRICITY

GETTING STARTED

I think I lostan electron!

Are yousure?

I’m positive!

How muchis a beer?

For you,no charge.

These two stories are based on the double meaning of thewords “positive” and “charge”.

a Look at the two extracts from a bilingual dictionary andunderline the appropriate translations.

b Can you explain why the stories are funny?

1

charge [´tʃɑ�d�] s. 1 spesa, onere, costo: free

of –, gratuito; admission –, prezzo d’ingresso;

charges forward, spese a carico del

destinatario; no – for packing, imballo

compreso � bank charges, commissioni

bancarie � – account, (amer.) conto aperto

(presso un negozio) 2 incarico: to be in – of,

assumere la direzione di, la responsabilità di �

official in –, funzionario incaricato; person in

–, addetto responsabile 3 sorveglianza, cura:

to be in s.o.’s –, essere sotto la sorveglianza di,

affidato alle cure di qlcu. 4 (dir.) accusa: to

bring a – against s.o., accusare qlcu.; he was

arrested on a – of murder, fu arrestato sotto

accusa di omicidio 5 (mil., elettr.) carica.pos-it-ive [´pɒzɘt�v] agg. 1 positivo: a –attitude towards life, un atteggiamento positivo,ottimistico nei confronti della vita; a – reply, unarisposta affermativa; a – result, un risultatopositivo 2 effettivo; concreto: he is a – nuisance,è proprio un seccatore, è un vero seccatore 3 preciso, definitivo: I gave you – instructions, tiho dato istruzioni precise �(dir.) – evidence, provadiretta, positiva 4 convinto, certo 5 (elettr.,mat.) positivo: p. electricity, elettricità positiva.

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3

Electrons flowing in a circuit

Bohr’s model atom

neutron chemicals nucleus cellproton positive terminal

electrons orbit conducting wire

neutron

negatively chargedcasing

electron flow

1.

2.

3.4.

5.

6.

7.8.

The words andexpressions in the box aresimilar to their Italianequivalents. In pairs, usethem to label the two figures.

2

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4

SECTION 1 ELECTRICITY

Focus on content

Focus on vocabulary

The atom and current electricityAll matter is made up of atoms but, as we cannot see them under the most powerful microscope,scientists construct models to explain and predict their behaviour. In 1913 a Danish physicist, NielsBohr, proposed a very simple model of the atom. In this model small electrons with negative elec-trical charge move in orbits around a central nucleus containing positively charged particles calledprotons and particles without charge called neutrons.

In a normal atom the negative charges on the elec-trons are exactly balanced by the positive charges onthe nucleus: we say that an atom in this state is neut-ral. The electrons which go round the nucleus staythere because opposite charges attract, that is, a pro-ton and an electron exert a force on each other whichpulls them together. The electrons are confined toorbits at fixed distances from the nucleus: each orbitcorresponds to a specific amount of energy carried bythe electrons in it. If an electron gains or loses energy,it can jump to the next orbit away from the nucleus ortowards it. The force of attraction of the nucleus getsweaker with distance, so the electrons in the most

Listen and read.3

The verbs in the box all appear in the text above.Use them in the correct form to complete thesesentences.

a There are plans to . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . a newbridge across the river.

b It is difficult to . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . the effects ofthat accident.

c He has . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . an interestingsolution to our problems.

d A solar panel . . . . . . . . . . . . . . . . . . . . . . . . . . . energy from the sun.e A conducting wire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . the casing

to the terminal.

Below are some more words from the text whichare similar to Italian. Find their opposites choosingfrom the words in the box.

a simple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

b central . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

c specific . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

d attraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

e external . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

f detached . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

g excess . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

attached complex generic internal lack peripheral repulsion

6

accumulate connect construct predict propose

5

Atomium, Brussels

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5

UNIT 1 Basic Electricity (1)

OVER TO YOU8Complete these descriptions.

a The structure of an atom.In an atom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . is a centralnucleus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . up of protons and. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A number of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

move in orbits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . it. The. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . of electrons in a normal atomis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . to the number of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

b How we obtain current electricity.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . electrons normally move at. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . among the atoms of a. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , but if we make them. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . in a uniform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

we obtain an . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . current.

Answer the following questions:

a Who was Niels Bohr?b What is the structure of Bohr’s atom?c When do we say that an atom is neutral?d What happens if an electron gains or loses

energy?

e When can an electron become a free electron?f How do free electrons move in a material?g How can we create an electric current in a dry

cell?

4

external orbits can easily be detached from the atom,either by collision or by an electric field. The detachedelectrons are called free electrons.

All materials contain some free electrons. Theymove among the atoms at random, but this move-ment is normally equal in all directions. Therefore, noelectrons are lost or gained by any part of the material.However, it is possible to make the electrons flow in auniform direction, creating what we call an electriccurrent.

A typical example of an electric current is that of adry cell. Because of the internal chemistry of the cell, the outer casing accumulatesan excess of free electrons, while the centre terminal has practically no freeelectrons. If we connect the casing and the terminal with a conducting wire,electrons will flow along the wire from the casing to the terminal, since they areattracted towards areas with a net positive charge.

Choose some of the words in exercise 6 tocomplete the following sentences.

a The electrons in the most . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

orbits are not easily detached from the atom,because the force of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . of thenucleus is very strong.

b The movement of free electrons is equal in alldirections. This means that there is no. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . or . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ofelectrons in any part of the material.

c Bohr’s model of the atom is still used todaybecause it is not very . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7

Niels Bohr

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6

SECTION 1 ELECTRICITY

Atomic and sub-atomic particles

You Ask. We Answer.What does matter really consist of?(Asked by Karen Johnson, 17, Gaysham Comprehensive School, Essex.)

This is one of the central problems of physics. We know that anatom is constituted by a nucleus which contains neutrons andprotons and by a cloud of electrons revolving around it. Is thisthe end of the story? No. Because protons and neutrons are notfundamental particles like electrons, but they have an internalstructure, they are composite particles. They seem to be com-posed of what we call “quarks”. So far we know of six quark types(scientists call them “ ”): up, down, strange, charm, topand bottom. However, only two of these quarks (up and down)are stable, and will not . The heavier quarks aren’t foundin nature and have only been observed in .

particle acceleratorsdecay

flavors

A Before reading the text, read thesestatements. Do you think they are true (T)

or false (F)? Discuss them with a partner.

T F1 Protons and neutrons are composite

particles of matter. � �2 Protons are made up of “quarks”. � �3 There are different types of quarks. � �4 “Gluons” orbit around the nucleus. � �

B Now read and check your answers.

C Some words are highlighted in the text. Write them next to their translation.

1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . rimbalza 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . prova 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e` dovuto a4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . decadere5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . colpiti6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . gusti7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . lega, tiene insieme8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . per quanto riguarda9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . acceleratori di particelle

9

Focus on skills

proton

neutron

quark

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7

UNIT 1 Basic Electricity (1)

D Answer the following questions:

a What is the traditional description of an atom?b Why is that description not good enough?c Are all quarks found in nature?d When do protons and neutrons reveal their

internal structure?e What are “gluons”?

E Choose the correct word(s)to complete the sentences.

a The movement of free electrons is responsible. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . current flow.

b An atom is composed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

fundamental and composite particles.c A nucleus is made . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . quarks and

gluons.d A lithium atom consists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . three

protons, three electrons and four neutronse A cell is constituted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

chemicals, an outer casing and a terminal. f The position of an electron around the nucleus is

due . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . its amount of energy.g These calculations are correct because they are

based . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . our measurements

by for of (x2) on to up of

LEXICAL CHUNKS

The proton is made up of two up quarks and a down quark(uud), while the neutron consists of one up quark and two downquarks (udd). of their existence is based on laboratoryexperiments. When protons and neutrons are with parti-cles that truly are fundamental (like electrons, photons etc.) theprotons and neutrons reveal their structure in the way the collid-ing particle .

So, you may think the nucleus is made up of up and downquarks. But that is not true either. There are also “gluons”, whichare the force that holds quarks together and are also responsiblefor the nuclear force that the nucleus together.

Is that all? No, not yet. Apart from the quarks that constitute thenucleons (i.e. neutrons and protons) there also exists a “sea ofquarks”, which continually appear and disappear: this quantum fluctuations.

So, a nucleus is quite a complicated thing. But you can say,fundamental particles , the nucleus is made up of

quarks and gluons…

(Answered by: Yasar Safkan, Ph.D., Software Engineer, Noktalar A.S., Istanbul, Turkey)

goas far as

is due to

binds

rebounds

struckProof

A proton

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You are on a 3-month language course in Londonand you have seen an advertisement for acomputer course in Time Out magazine.Call the school and ask for some information aboutthe courses:

e.gHow long... last?What time... ?How much... ?N.B. You would like to start as soon as possible. Your hotel fax number is 020-7981 9211.

Student A

1. First you are the switchboard operator.Put the caller through to the director of studies.

2. Now you are the director of studies.Answer the caller’s questions using theinformation in the prospectus below.Then offer to send the caller a full prospectus withdetails of fees.

Student B

8

SECTION 1 ELECTRICITY

Focus on skills

A Complete thephone call using the expressions in the box.

* Hello, Ryman Electronics. Can I help you?– Hello, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (1)

about your products.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (2), please, . . . . . . . . . . . . . . . . . . . . . . . . . (3)

Sarah Harper in the Sales Department.** Sales department. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (4).– Hello, this is Michael Roberts of Evans

Engineering.

** Hello, Mr Roberts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ?(5). – Well, I saw an advertisement for your products in

Electronics Weekly and I’d like to make someenquiries about them.

** Yes, of course. Which range of products . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ?(6). – Mainly the HV300s.** Well, I can send you a full catalogue and price

list...– Thank you. That’s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (7)** . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (8).

Can I have your address,please?

– Yes, of course. It’s...

you’re welcome I’d like some information I’ll put you through to very kind of you

Sarah Harper speaking are you interested inwhat can I do for you hold on

MAKING A PHONE CALL10

Act out a similar telephone conversation with your partner using the guidelines below.ROLE PLAY11

International Education

at its best!

BUSINESS ADMINISTRATION

COMPUTING & IT • TRAVEL & TOURISM

MODERN LANGUAGES

ACCOUNTANCY & FINANCE

SECRETARIAL STUDIES

For details call FREE on 0800 980 1549

or write to: Evedale College,

The Central Admissions Office,

24-26 Oxford Street, London W1N 9FL

EvedaleCollege

Evedale College24-26 Oxford Street, London W1N 9FL

0800 980 1549

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Computing and IT Courses

DURATION: 2 months or 4 months (New courses start on the first Monday of each month.)

TIMES: 3 times a week: Mon, Wed, and FriChoice of early afternoon course (2pm-5pm)or evening course (7pm-10pm)

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B Now listen to the complete conversation and check your answers.

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9

UNIT 1 Basic Electricity (1)

Grammar Extension

How many of these words do youremember in English?

atomo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

attrazione . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

carica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

corrente elettrica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

elettricità . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

elettrone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

filo (elettrico) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

fisica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

fluire, flusso . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

materia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

neutrone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

nucleo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

orbita . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

particella elementare/composta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

protone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Translate this sentence into Italian.

a When the outer casing of a dry cell is connectedto the centre terminal by means of a conductingwire, electrons will flow along the wire from thecasing to the terminal, that is, from negative topositive.

Translate these sentences into English.

b In un atomo ci sono protoni, neutroni ed elettroni.Il nucleo è costituito da protoni e neutroni, mentre(= while) gli elettroni si muovono in orbita attornoad esso.

c I gluoni sono particelle subatomiche. Ci sono sei“gusti” di gluoni; tuttavia solo i gluoni “up” e“down” si trovano in natura.

TRANSLATIONKEY WORDS

Check your progress

Logical connectorsA These are logical connectors from the texts you have read. Match the pairs with the same meaning. Then writetheir Italian translation(s), choosing from those given in the box.

therefore but . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

since so . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

however as . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

B Choose the correct connectors in these sentences.

1 Atoms cannot be seen even under the most powerful microscopes; but/therefore, physicists constructmodels of them.

2 Since/However the force of attraction of the nucleus gets weaker with distance, the electrons on theexternal edge of an atom are held in orbit rather loosely.

3 There are six quark types. However/So, only two of these quarks are stable and will not decay. 4 Electrons move in fixed orbits. But/Therefore, if they gain extra energy, they can jump to the next orbit

away from the nucleus.5 Electrons are attracted towards areas with a net positive charge. So/As, if we connect the casing and the

terminal by means of a conducting wire, they will flow along the wire from the casing to the terminal.

perciò/quindi poichè/siccome tuttavia/ma

C Form complete sentences using the connectors in the middle.

1 I’m not very good at Maths as a I am the only one who knows him.2 It’s raining hard and b I have to ask for my father’s help.3 I’m picking Mr Gibson up at the station so c I don’t want to take a taxi.4 It’s already 7 o’clock but d Peter is not here yet.

tuttavia/ma

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