Acknowledgements

The authors and publishers acknowledge the following sources of copyright material and are grateful for the permissions granted. While every effort has been made, it has not always been possible to identify the sources of all the material used, or to trace all copyright holders. If any omissions are brought to our notice, we will be happy to include the appropriate acknowledgements on reprinting and in the next update to the digital edition, as applicable.

Key: Int = Intro, Lit = Literature, SU = Starter Unit; U = Unit

Grammar Worksheets

Photography
The following photographs are sourced from Getty Images.

SU: monkeybusinessimages/iStock/Getty Images Plus; rasslava/iStock/Getty Images Plus; pagadesign/E+; U1: CasarsaGuru/iStock/Getty Images Plus; YinYang/iStock/Getty Images Plus; gbh007/iStock/Getty Images Plus, U2: Wong Sze Fei/EyeEm; www.mileswillis.co.uk/Moment/Getty Images Plus; monkeybusinessimages/iStock/Getty Images Plus; U3: Sam Edwards/OJO Images; Assia Doufar/EyeEm; kajakiki/E+; U4: Francisco Martín Martin Imagenes Naturales/500px; Syldavia/iStock/Getty Images Plus; Fuse/Corbis; U5: Nick David/Photodisc; mustafagull/E+; Peter Dazeley/The Image Bank/Getty Images Plus; U6: InnaPoka/iStock Editorial/Getty Images Plus; piranka/iStock/Getty Images Plus; Caiaimage/Robert Daly/OJO+; U7: Sergey Nazarov/iStock/Getty Images Plus; Bruno De Hogues/Stockbyte; Rainer Grosskopf/Photolibrary/Getty Images Plus; U8: Heritage Images/Hulton Fine Art Collection; bruev/iStock/Getty Images Plus; Dougal Waters/Photographer's Choice RF; U9: Bloom Productions/Taxi/Getty Images Plus; Photography taken by Mario Gutiérrez/Moment; Thomas Barwick/Stone/Getty Images Plus.

Vocabulary Worksheets

Photography
The following photographs are sourced from Getty Images.

SU: StudioEDJO/iStock/Getty Images Plus; PLG/iStock/Getty Images Plus; VitaliiPhoto/iStock/Getty Images Plus; Anthony Bradshaw/Photodisc; IGOR SVETLICHNYI/iStock/Getty Images Plus; jpkirakun/Stock/Getty Images Plus; pamspix/iStock/Getty Images Plus; U1: Wilaipon Pasawat/EyeE; Mike Kemp; U2: mikroman6/Moment; monkeybusinessimages/iStock/Getty Images Plus; U3: maki_shmaki/iStock/Getty Images Plus; U4: Asanka Brendon Ratnayake/Lonely Planet Images; John Wood Photography/Taxi; asiseeit/E+; Jeff Dunn/Photolibrary/Getty Images Plus; Bill Stormont/Corbis; RichLegg/E+; gchutka/E+; U5: YangYin/E+; Sergey05/iStock/Getty Images Plus; Julija Svetlova/EyeEm; Kate Davis/Dorling Kindersley; Mark Griffin/EyeEm; Grafimania/iStock/Getty Images Plus; Astronaut Images/Caiaimage; U6: toos/E+; Westend61; AntonioGuillem/iStock/Getty Images Plus; U7: Maksym Rudoi/iStock/Getty Images Plus; TimeStopper/Moment; Cavan Images; COMiCZ/iStock/Getty Images Plus; Prathan Chorruangsak/EyeEm; Dimitri Otis/Photographer's Choice/Getty Images Plus; Cultura RM Exclusive/Dan Dunkley/Getty Images Plus; U8: Shannon Fagan/DigitalVision; leventince/E+; Westend61; Chris Ryan/Caiaimage; AJ_Watt/E+; Cultura RM Exclusive/Jason Butcher/Getty Images Plus; Jasmin Merdan/Moment; U9: www.anacuba.com/Moment/Getty Images Plus; Punnarong Lotulit/EyeEm; Jonathan Gelber; Snob Mine Olivari/EyeEm; Hill Street Studios/DigitalVision; Michael Heim/EyeEm; George Shelley/Corbis; Nisian Hughes/Stone; Nigel Roddis/Getty Images News.

Communication Worksheets

Photography
The following photographs are sourced from Getty Images.

U1: Photo and Co/Photographer's Choice/Getty Images Plus; Armation74/iStock/Getty Images Plus; vm/E+; WLDavies/E+;Phil Boorman/Cultura; Edward Crawford/Moment; Elena Peremet/Moment; Westend61; John Howard/DigitalVision; Erik Dreyer/Stone; Jupiterimages/BananaStock/Getty Images Plus; Cultura RM Exclusive/Spark Photographic/Getty Images Plus; U2: By Eve Livesey/Moment; larigan - Patricia Hamilton/Moment; Rob Stothard/Stringer/Getty Images News; U4: Sarah Saratonina/EyeEm; veselinaalexandrova/RooM; Juanmonino/E+; gbh007/iStock/Getty Images Plus; Ed Bock/Corbis/Getty Images Plus; Esther Li/EyeEm; U5: in4mal/iStock/Getty Images Plus; onurdongel/E+; U6: Mike Kemp; anmbph/iStock/Getty Images Plus; lechatnoir/E+; Hero Images; pastorscott/E+; Milkos/iStock/Getty Images Plus; U8: PamelaJoeMcFarlane/iStock/Getty Images Plus; eli_asenova/E+; U9: SensorSpot/Vetta; Lane Oatey/Blue Jean Images; Nisian Hughes/Stone; Peathegee Inc/Blend Images.

Literature Worksheets

Lit: Lisbeth Hjort/Cultura/Getty Images Plus.

Project Templates

Photography
The following photographs are sourced from Getty Images.

Int: Hero Images; Steve Debenport/E+; code6d/E+; ilyast/DigitalVision Vectors; FatCamera/E+; RobinOlimb/DigitalVision Vectors; RaStudio/iStock/Getty Images Plus; Wavebreakmedia/iStock/Getty Images Plus; pbombaert/Moment; Nina Dermawan/Moment Mobile; Wibowo Rusli/Lonely Planet Images; anactor/iStock/Getty Images Plus; Michael H/DigitalVision; Coco Flamingo/Imagezoo; portishead1/E+; mediaphotos/iStock/Getty Images Plus; Indeed.
The following photographs are sourced from other libraries/sources.
Int: Kirby Wu; Malini Images/Alamy Stock Photo.

Illustrations
Int: Jose Rubio.

Cover design: Chefer. Cover illustration: Andrés Martínez.

Video Worksheets/Videos

Documentaries

Photography
All photographs are sourced from Getty Images./ U1.1: Print Collector/Hulton Archive; Hulton Archive; Science & Society Picture Library; Bettmann; Hulton Deutsch/Corbis Historical; Fox Photos/Hulton Archive; George Rinhart/Corbis Historical; Chris Hunter/Corbis Historical; Topical Press Agency/Hulton Archive; Daily Herald Archive/SSPL/Hulton Archive; De Agostini Picture Library; Fred Morley/Hulton Archive; Malcolm Dunbar/Picture Post; PhotoQuest/Archive Photos; John Dominis/The LIFE Picture Collection; Mikael Vaisanen/Corbis; Maskot; Eric Audras/ONOKY/Getty Images Plus; U1.5: Ami Vitale/Getty Images News; DreamPictures/The Image Bank; Dinodia Photo/Corbis NX; The India Today Group; MicrovOne/iStock/Getty Images Plus; Universal Images Group; AFP; NurPhoto; Hindustan Times; STR/AFP; Jonathan Torgovnik/Getty Images News; Frédéric Soltan/Corbis News; misuma/iStock/Getty Images Plus; DreamPictures/The Image Bank; Marc Romanelli; bjones27/E+; U2.1: Werner Forman/Universal Images Group; DEA/G. DAGLI ORTI/De Agostini; Print Collector/Hulton Archive; Independent Picture Service/Universal Images Group; Leemage/Universal Images Group; Christophel Fine Art/Universal Images Group; De Agostini/G. Sioen/De Agostini Picture Library; DEA/G. LOVERA/De Agostini; Planet Observer/Universal Images Group; Universal Images Group; Science & Society Picture Library; DEA/W. BUSS/De Agostini Editorial; DEA/C. SAPPA/De Agostini Editorial; phanasitti/iStock/Getty Images Plus; Betsie Van Der Meer/Taxi; Anton Petrus/Moment Video RF; Elenathewise/iStock/Getty Images Plus; U3.1: Howard Kingsnorth/The Image Bank/Getty Images Plus; artpartner-images/Photographer's Choice/Getty Images Plus; Tony Cordoza/Photographer's Choice; © Roland Dan/Moment; Olga Kashurina/iStock/Getty Images Plus; De Agostini/L. Romano/De Agostini Picture Library/Getty Images Plus; DEA PICTURE LIBRARY/De Agostini Picture Library/Getty Images Plus; Haywood Magee/Picture Post; Nastasic/DigitalVision Vectors; China Photos/Getty Images News; Biblioteca Ambrosiana/De Agostini Picture Library/Getty Images Plus; Culture Club/Hulton Archive; Print Collector/Hulton Fine Art Collection; ullstein bild Dtl; United Archives/Universal Images Group; U3.5: Planet Observer/Universal Images Group; James Merrell/Dorling Kindersley/Getty Images Plus; Horst Sollinger; Bo Zaunders/Corbis Documentary; De Agostini/V. Giannella/De Agostini Picture Library; Juan Carlos Munoz/The Image Bank; Education Images/Universal Images Group; Jonathan Smith/Lonely Planet Images/Getty Images Plus; Ashraful Arefin photography/Moment; baobao ou/Moment; Image Source/DigitalVision; U4.1: Joe Sohm/Visions of America/Universal Images Group; Arthur Tilley/The Image Bank/Getty Images Plus; Hill Street Studios/DigitalVision; Jose Luis Pelaez Inc/DigitalVision; sdominick/E+; Andia/Universal Images Group; fstop123/E+; Rpsycho/E+; U5.1: junlongyang/Moment/Getty Images Plus; G&M Therin-Weise; Xiaoyang Liu/Corbis Documentary; Keren Su/China Span; DEA/C. DANI I. JESKE/De Agostini; SOPA Images/LightRocket; Marc Dozier/Corbis NX; Andrew Watson/Photolibrary; Andrew Watson/Lonely Planet Images; John W Banagan/Lonely Planet Images; Zack Seckler/The Image Bank; Westend61; U5.5: Barcroft Media; iannomadav/iStock/Getty Images Plus; Peter Ptschelinzew/Lonely Planet Images; TED MEAD/Photolibrary; Tim Ridley/Dorling Kindersley; Aurora Rodriguez/Photolibrary; Glow Décor/Glow; Steve Wisbauer/Photolibrary; Antonia Tozer/AWL Images; Thierry Falise/LightRocket; Timothy Allen/Photolibrary; Mathias Rhode/iStock/Getty Images Plus; Nick Ledger/AWL Images; U6.1: zak00/DigitalVision Vectors; Designer_things/iStock/Getty Images Plus; Piotrurakau/iStock/Getty Images Plus; bonezboyz/iStock/Getty Images Plus; VCG/Visual China Group; TPG/Getty Images Entertainment; ED JONES/AFP; Bloomberg; AFP; Barcroft Media; Marcel Hlscher/EyeEm; Thomas Northcut/Photodisc; Oppdowngalon/iStock/Getty Images Plus; U7.1: Jean-Pierre BOUCHARD/Gamma-Rapho; Jan Stromme/Stone; JOHN READER/SCIENCE PHOTO LIBRARY; Science Picture Co/Collection Mix: Subjects; Antony Giblin/Lonely Planet Images; Roman; Steven Puetzer/The Image Bank; Universal History Archive/Universal Images Group; Museum of Flight Foundation/Corbis Historical; Fox Photos/Hulton Archive; H. Armstrong Roberts/ClassicStock/Archive Photos; Bettmann; Dave Bradley Photography/The Image Bank; Jeffrey Hamilton/Stone; Science & Society Picture Library; DEA PICTURE LIBRARY/De Agostini; De Agostini Picture Library; Print Collector/Hulton Archive; Apic/Hulton Archive; Justin Sullivan/Getty Images News; H.ArmstrongRoberts/ClassicStock/Archive Photos; Sascha Steinbach/Getty Images News; U7.5: YOSHIKAZU TSUNO/AFP; TOSHIFUMI KITAMURA/AFP; ANTONY DICKSON/AFP; Ekkasit919/iStock/Getty Images Plus; AFP; Bloomberg; KAZUHIRO NOGI/AFP; NurPhoto; Kurita KAKU/Gamma-Rapho; John S Lander/LightRocket; JIJI PRESS/AFP; Yamaguchi Haruyoshi/Corbis News; U8.1: Hulton Archive; Time Life Pictures/The LIFE Picture Collection; U9.1: Lorne Thomson/Redferns; Hiroyuki Ito/Hulton Archive; Lars Baron; Ken Hively/Los Angeles Times; AJ_Watt/E+; BSIP/UIG/Universal Images Group; U9.5: Johannes Simon/Getty Images News; Peter von Felbert/LOOK-foto; Evans/Hulton Archive; Bruce Yuanyue Bi/Lonely Planet Images/Getty Images Plus; Tristar Media/Getty Images Entertainment. Video All video clips are sourced from Getty Images. U1.1: Archive Farms/Archive Films: Creative; Grinberg, Paramount, Pathe Newsreels/Sherman Grinberg Library; Bettmann; fotomy/Creatas Video+; Petrified Films/Archive Films: Creative; Hearst Newsreel; Archive Films: Creative; Mr. Big Film/Verve; Mr. Big Film/one80; Curious Cumulus Productions/Archive Films: Creative; StockFilmdotCOM/Creatas Video; gorodenkoff/Creatas Video; Froomer Pictures Ltd./Image Bank Film: Signature; shironosov/Creatas Video; Eternity In An Instant/DigitalVision; VladGans/Creatas Video; Frames Footage/Verve; U1.5: nmlfd/Creatas Video; Yamato1987/Creatas Video; dpmike/Creatas Video; Bryan and Wendy Mullennix/Verve+; Rufus Blackwell/Image Bank Film; Studio DB/Photodisc; Gavin Hellier/Image Bank Film; ITN; ImagesBazaar; Pierre Ogeron/DigitalVision; Craig McCourry/Verve+; de Lossy/Corbis Video; Aerial Filmworks; Camp4 Collective; viafilms/Creatas Video+; gawrav/Vetta; ImagesBazaar/Photolibrary Video; Shoreditch Park Studios/Image Bank Film; Stewart Cohen Pictures; Stewart Cohen Pictures/one80: Signature; opal2/Creatas Video+; JosuOzkaritz/Creatas Video+; WOWstockfootage Trust/Corbis Video; Stewart Cohen Pictures/Image Bank Film: Signature; simonkr/Vetta; haizon/Vetta; ImagesBazaar/Verve; Alexpunker/Creatas Video+; Bob Chappell and John Alfirevich/Image Bank Film; selected-takes/Vetta; U2.1: Naga Film/Verve; HOPE PRODUCTIONS/Yann Arthus Bertrand; Rick_Jo/Creatas Video; Gallo Images/Media Village Productions (Pty) Ltd/DigitalVision; A&E Television Networks/Archive Films: Creative; Juan Carlos Munoz/DigitalVision; Discovery Access; Merlinus74/Creatas Video+; Chris Allingham/Verve; A&E Television Networks/Image Bank Film; WLV Stock/DigitalVision; Gal Productions/Image Bank Film; glowonconcept/Creatas Video+; Zachary Michael Boggs/Image Bank Film; RPM Media Inc - Roberto & Christina Mitrotti/Image Bank Film; Chris Allingham/Image Bank Film; Travel Productions/Image Bank Film; Clippn/Getty Images Editorial Footage; Peter Adams Photography Ltd./Verve; Black Pearl/Corbis Video; ugurhan/Creatas Video; Getty Images Editorial Footage; U3.1: ftgipsy/Creatas Video+; Stusya/Creatas Video+/Getty Images Plus; Daedalum/Creatas Video; A&E Television Networks/Archive Films: Creative; Regine Mahaux/Image Bank Film: Signature; Gardner Films Inc/Image Bank Film; Gsmotion/Photolibrary Video; iStock_Oles/Creatas Video+; mack2happy/Creatas Video; Discovery Access; wyoosumran/Creatas Video+/Getty Images Plus; creativeballs/Vetta; Sylvain Sonnet/Image Bank Film; 02lab/Creatas Video+/Getty Images Plus; OmniMovi Ltd/Corbis Video; Japan Memoirs/Verve; BlackBodyRadiation/Creatas Video; Nisian Hughes/Image Bank Film: Signature; pigprox/Creatas Video; skynesher/Vetta; Motortion/Creatas Video+/Getty Images Plus; franckreporter/Creatas Video; gorodenkoff/Creatas Video+/Getty Images Plus; U3.5: Gerard Lacz Images/Image Bank Film; slowmotiongli/Creatas Video+; maxximmmCreatas Video+; StockSeller_ukr/Creatas Video+/Getty Images Plus; proBAKSTER/Creatas Video+/Getty Images Plus; Juan Carlos Munoz/Image Bank Film; fotospring/Image Bank Film; simonkr/Vetta; Johnce/Creatas Video; spyderskidoo/Creatas Video; giddyuptimelapse/Creatas Video; captamotion/Creatas Video; qlproduction/Creatas Video; Ruben Earth/Moment Video RR; simonkr/Creatas Video; Aldo Pavan/Photodisc; freemixer/Creatas Video; shutter_m/Creatas Video; Motortion/Creatas Video+; Aldo Pavan/DigitalVision; Stereo Lab Films/Image Bank Film: Signature; TaManKunG/Creatas Video; Sitti_/Creatas Video; GM Stock Films/Creatas Video; Francis Manceau/DigitalVision; Discovery Access; SimonSkafar/Creatas Video; Molostock.com/Creatas Video; Train_Arrival/Creatas Video+/Getty Images Plus; U4.1: Pigeon Productions Inc./Image Bank Film; Milmotion/Getty Images Editorial Footage; kali9/Vetta; The Lighthouse Film Co, Inc./Lighthouse Films; Ariel Skelley/Iconica Video: Signature; Yellow Dog Productions Inc./Image Bank Film: Signature; Thomas Barwick/Iconica Video: Signature; shironosov/Creatas Video+/Getty Images Plus; Steve Debenport/Creatas Video; INT; maradek/Creatas Video+/Getty Images Plus; Mark Andersen/DigitalVision; SolStock/Creatas Video; Thomas Barwick/Image Bank Film: Signature; David Fortney/Iconica Video: Signature; xijian/Creatas Video; Toa55/Creatas Video+/Getty Images Plus; MachineHeadz/Creatas Video+/Getty Images Plus; Pressmaster/DigitalVision; Meridian Studios/Verve; SuburbanRhapsody/Creatas Video; ILLYCH/Creatas Video+/Getty Images Plus; U5.1: Wayne Herron/Creatas Video; Stock Footage, Inc./Verve+; gogoloji/Creatas Video; Dmitro2009/Creatas Video+/Getty Images Plus; xenotar/Creatas Video; The Lighthouse Film Co, Inc.; Bronek Kaminski/one80; Geoff Tompkinson/one80; itsskin/Creatas Video; Curt Walheim/Iconica Video; DroneBase/DigitalVision; Discovery Access; tdub303/Creatas Video; luckpics/Creatas Video; Caiafilm; Counter/Photodisc; Jacky/Creatas Video+; Dovidovich/Creatas Video+; Martin Puddy/Image Bank Film; Aerial Filmworks; Toshi Sasaki/Image Bank Film; Bill Bachmann/Image Bank Film; zhuzhu/Creatas Video+; Onfokus/Creatas Video; milehightraveler/Creatas Video; Juan Carlos Munoz/DigitalVision; Fondation GoodPlanet/Rights-ready; Mark Andersen/Photolibrary Video; Marc Romanelli/Image Bank Film; Revelation/DigitalVision; Stockshare/Creatas Video; The Time Lapse Company/Image Bank Film; Multi-bits/Image Bank Film; AclaraPromotions/Creatas Video+; Samuel Magal/Photolibrary Video; Peter John Phipp/Image Bank Film; ITN; PhotosIndia/Image Bank Film; Onyx Media, Llc - Footage; U5.5: Stanislav Tiplyashin/DigitalVision; Visual_Bricks/Creatas Video+; Multi-bits/Image Bank Film; Craig McCourry/Verve+; Anton Petrus/Moment Video RF; Deluxe Photo/Image Bank Film; A&E Television Networks/Image Bank Film; Copyright Unscripted Films/Image Bank Film; Do Diligence Inc./Image Bank Film: Signature; Pavel Gospodinov/Photodisc; Human/Fondation GoodPlanet/Yann Arthus-Bertrand; Fondation GoodPlanet/Yann Arthus-Bertrand; zgr_pro/Creatas Video+; Chris Bedyk/Image Bank Film; Pavel Gospodinov/Image Bank Film; Laoshi/Creatas Video+; U6.1: Robin Beckham/Creatas Video; hanieriani/Creatas Video+; STK Pictures/Image Bank Film; Mark Andersen/Photolibrary Video; Bplanet/Creatas Video; Beyond Our Reality Productions Inc./one80: Signature; Ariel Skelley/Image Bank Film: Signature; Serhii Brovko/Creatas Video+; motionxcom/Creatas Video+; monkeybusinessimages/Creatas Video+; tawattiw/Creatas Video; Thomas Barwick/Image Bank Film: Signature; Steve Debenport/Creatas Video; shironosov/Creatas Video+; piola666/Vetta; Laurence Dutton/Vetta; saskami/Creatas Video; simonkr/Creatas Video; seb_ra/Creatas Video+; roshinio/Creatas Video; Rubberball/Verve+; ITN; guy113/Creatas Video; jhorrocks/Creatas Video+; konstantynov/Creatas Video; Elcurado/Creatas Video; Guillaume749/Vetta; Multi-bits/DigitalVision; gorodenkoff/Creatas Video+; Ariel Skelley/Iconica Video: Signature; WW News/Image Bank Film; Galloabraham/Image Bank Film: Signature; Erik Van Ingen/Photodisc; JesseAnthony/Creatas Video+; JaimeByrd/Creatas Video+; SimonSkafar/Vetta; SimonSkafar/Creatas Video; iprogressman/Creatas Video+; ImagesBazaar/Photolibrary Video; Andersen Ross/Verve+; Stusya/Creatas Video+; iprano/Creatas Video+; U7.1: Ramil Shakirov/Creatas Video+; Guido Mieth/Image Bank Film; alisbalb/Creatas Video+; Oxford Scientific Films/Photolibrary Video; Wishing Tree Productions/Image Bank Film: Signature; John Lamb/Iconica Video: Signature; Thomas Barwick/Image Bank Film: Signature; rachwal81/Creatas Video+; Robin Beckham/Creatas Video; opal2/Creatas Video+; fotogenicstudio/Creatas Video; Science & Society Picture Library; Trompinex/Creatas Video+; ITN; Onyx Media, Llc - Footage/Archive Films: Editorial; Film Audio Services - Footage/Archive Films: Editorial; Archive Films/; Warner Bros. Studios/Warner Bros. Entertainment; 1.21 Gigawatt Productions/Archive Films: Creative; ITN Archive Limited/Archive Films: Editorial; Joe Jennings/Image Bank Film: Signature; Stephen Marks Inc./Photolibrary Video; GK Hart-Vikki Hart/Image Bank Film; pictafolio/Creatas Video; Bottom Line Productions/Image Bank Film: Signature; Alexandrea Day/Getty Images Editorial Footage; The7Dew/Vetta; Colin Anderson Productions pty ltd/Image Bank Film: Signature; U7.5: Stereoscreen Audiovisual Productions GmbH/U/Image Bank Film; Bunch_Bundle/Creatas Video+; Bavorndej/Creatas Video+; Jgalione/Creatas Video; Hal Bergman/Image Bank Film; NurPhoto/Getty Images Editorial Footage; Zhang Peng/Getty Images Editorial Footage; Caiafilm/Creatas Video; grdenis/Creatas Video+; Tomohiro Ohsumi/Getty Images Editorial Footage; OpticFlow/Creatas Video; zefart/Creatas Video+; SVTeam/Creatas Video+; Science Photo Library/Photolibrary Video; xenotar/Creatas Video; Captamotion/Image Bank Film; Press Association; Sean Gallup/Getty Images Editorial Footage; payphoto/Creatas Video+; vichie81/Creatas Video; Baloncici/Creatas Video+; Ramin Talaie/Corbis Video; Sky News/Film Image Partner; Tribune Broadcasting - Anna Burkart; Multi-bits/Image Bank Film; JK1991/Creatas Video; Derek Sellens/Creatas Video+; serg3d/Creatas Video; nikkino/Creatas Video+; Copyright Unscripted Films/Image Bank Film; loveguli/Creatas Video; Spotmatik/Creatas Video+; shin28/Creatas Video+; Matt Cardy/Getty Images Editorial Footage; motionxcom/Creatas Video+; pixone/Creatas Video+; U8.1: NASA Images Archiving LLC/Image Bank Film; NASA - Footage/Archive Films: Editorial; Silverwell Films/Archive Films: Editorial; NASA/Photolibrary Video; Blooms-Studio/Creatas Video+; Wavebreakmedia/Creatas Video+; Dkosig/Creatas Video; Onyx Media, Llc - Footage/Archive Films: Editorial; StockSeller_ukr/Creatas Video+; hoozone/Creatas Video; Onyx Media, Llc - Footage/Getty Images Editorial Footage; wojteKolakowski/Creatas Video; silverkblack/Creatas Video+; dtiberio/Creatas Video+; Lead Pipe Productions Pty Ltd/Image Bank Film; zgr_pro/Creatas Video+; bo1982/Creatas Video+; Camp4 Collective/one80; Witthaya/Creatas Video; cinejinn/Creatas Video+; Gregory Christopher Lindsey/Image Bank Film; Counter/Image Bank Film: Signature; Ariel Skelley/Verve+; RoosterHD/Creatas Video; romansu/Creatas Video+; PawelRut/Vetta; Assembly/Image Bank Film: Signature; Simonkr/one80: Signature; Caiafilm/Creatas Video; dualstock/Creatas Video+; Photitos2016/Creatas Video+; Marc Romanelli/Verve; Stock Footage, Inc./Photolibrary Video; Caiafilm/Vetta; John McBride & Company Inc./Iconica Video: Signature; Dennis Welsh/Image Bank Film: Signature; mack2happy/Creatas Video; Ascent Xmedia/Image Bank Film: Signature; James Carman/Image Bank Film: Signature; Wishing Tree Productions/Image Bank Film: Signature; Klaus Vedfelt/one80: Signature; Mark Andersen/Photolibrary Video; The Lighthouse Film Co, Inc./Lighthouse Films; asiseeit/Vetta; FootageUA/Creatas Video+; Wayne Herron/Creatas Video; Thomas Barwick/Image Bank Film; LeoPatrizi/Creatas Video; petekarici/Creatas Video; ImagesBazaar/Photolibrary Video; CHBD/Creatas Video; SolStock/Vetta; U9.1: signarius/Creatas Video+; ABC Entertainment Marketing/ABC Studios; rockptarmigan/Creatas Video+; Joseph Kelly/Creatas Video+; flavioc77/Creatas Video; VIDEODIVE/Creatas Video+; RubberBall Productions LLC/Photolibrary Video; Christian Ender/Image Bank Film; Erstudiostok/Creatas Video+; haoliang/Creatas Video; SrdjanPav/Creatas Video; Pigeon Productions Inc./Verve; Creatas Video; Nektarstock/Creatas Video+; xiaomuyu/Creatas Video; silverkblack/Creatas Video+; Konstantin Potseluev/Creatas Video+; Art Wolfe Travels to the Edge/Image Bank Film; Pavel Gospodinov/Image Bank Film; filipefrazao/Creatas Video+; Stewart Cohen Pictures/Image Bank Film: Signature; Tivoli Entertainment LLC/Image Bank Film: Signature; Discovery Access; Sky News/Film Image Partner; ITN; kali9/Creatas Video; Ariel Skelley/Image Bank Film: Signature; dream_one/Creatas Video+; Stanislav Tiplyashin/Image Bank Film; Ranta Images/Creatas Video+; Steve Debenport/Creatas Video; sircco/Creatas Video; Blink Tv/one80; The Lighthouse Film Co, Inc./Lighthouse Films; TomIraci/Creatas Video+; studyoritim/Creatas Video; da-kuk/Creatas Video; Studia72/Creatas Video+; eclipse_images/Creatas Video; slavemotion/Creatas Video; Bob Thomas/Image Bank Film; seb_ra/Creatas Video+; Silver555/Creatas Video+; mikiell/Creatas Video+; Steve Debenport/Vetta; Mark Andersen/Image Bank Film: Signature; Ariel Skelley/Iconica Video: Signature; thaiview/Creatas Video; monkeybusinessimages/Creatas Video+; Johnce/Vetta; Caiafilm/Creatas Video; HeroImagesFootage/Creatas Video; Franz Recktenwald/Corbis Video; Arthur Cauty/Moment Video RF; U9.5: Wavebreak Media Ltd./Verve+; Media Trading Ltd/Creatas Video; shironosov/Creatas Video+/Getty Images Plus; Do Diligence Inc./Image Bank Film: Signature; Master_Video/Creatas Video+/Getty Images Plus; perinjo/Vetta; Mark Andersen/Photolibrary Video; Julian Mydla/Creatas Video+/Getty Images Plus; Wolodymyr Black/Creatas Video+/Getty Images Plus; Obermeyer Productions Inc./one80; creuxnoir/Creatas Video+/Getty Images Plus; Captamotion/Image Bank Film; Robert Harding Video/Photolibrary Video; Peter von Felbert/LOOK-foto; Philipp Guelland/Getty Images News; Smithsonian; Alexander Hassenstein/Getty Images Editorial Footage; Geoff Tompkinson/Iconica Video; Redline Enterprises Munich/Image Bank Film; footagefactory/Image Bank Film; Rick Steves/Image Bank Film; querbeet/Creatas Video; Tivoli Entertainment LLC/Iconica Video; Caiafilm/Vetta; Jecapix/Creatas Video; © by Martin Deja/Moment Video RR; querbeet/Vetta; Sony Pictures Entertainment/Image Bank Film.

Audio
All audio clips are sourced from Getty Images.

U1.1: Shayan Mirza/SoundExpress; Aymen Khalifa/SoundExpress; Francesco Biondi/SoundExpress; piccadillyCircus/SoundExpress; U1.5: mitja mithans/SoundExpress; Sujay Govindaraj/SoundExpress; Derrik Jordan/SoundExpress; Sujay Govindaraj/SoundExpress; U2.1: Michael Toland/SoundExpress; RCummins/SoundExpress; Sujay Govindaraj/SoundExpress; Sujay Alexander Rybakov/SoundExpress; U3.1: Music for your Media/SoundExpress; Asim Tamer Tarhan/SoundExpress; Doron Hanochi/SoundExpress; Simone Manuli/SoundExpress; Purple Planet/SoundExpress; DZMITRY CHARNYSHOU/SoundExpress; U3.5: DeepBlueMusic/SoundExpress; mitja mithans/SoundExpress; LARRY CASTLE/SoundExpress; RFM/SoundExpress; U4.1: Hyawatta/SoundExpress; Stuart Geerts Entertainment/SoundExpress; Joseph Rusnak/SoundExpress; U5.1: RFM/SoundExpress; Erika_Gonzalez/SoundExpress; Cedric Hommel/Sound Effects; Sungtae Kim/SoundExpress; U5.5: Sergey Chetvertnykh/SoundExpress; michelangelo oprandi/SoundExpress; Sergii Pavkin/SoundExpress; SnowMusicStudio/SoundExpress; U6.1: Super Adventure Club/SoundExpress; Alekss Hercbergs/SoundExpress; RFM/SoundExpress; Andrea Bellina/SoundExpress; Vitaliy Pushchyn/SoundExpress; U7.1: Kevin King/SoundExpress; Karol Sabat/SoundExpress; Fedor Alekseev/SoundExpress; Lusky/SoundExpress; Sergey Chuprina/SoundExpress; U7.5: juqboxmusic/SoundExpress; Sergii Pavkin/SoundExpress; NeoCortex/SoundExpress; Sujay Govindaraj/SoundExpress; Dmitriy Shironosov/SoundExpress; U8.1: Ethereal Motion/SoundExpress; Cuttlefish Music/SoundExpress; sashqxxx/SoundExpress; U9.1: Dan Roundhill/SoundExpress; Erika_Gonzalez/SoundExpress; Ben Harris/SoundExpress; Ladislav Weyrostek/SoundExpress; Levendigheid/SoundExpress; piccadillyCircus/SoundExpress; Francesco Biondi/SoundExpress; juqboxmusic/SoundExpress; U9.5: Zofia Pawlaczek/Sound Effects by Getty Images; Derridon/Sound Effects by Getty Images; David Seeley/Sound Effects by Getty Images; Igor Dvorkin/SoundExpress; MentorRecords/SoundExpress; piccadillyCircus/Sound Effects by Getty Images; Andreas Furxer/SoundExpress.

Video produced by Lucentum Digital.

Grammar Vlogs

Photography
All photographs are sourced from Getty Images.

SU.1: Colin Anderson Productions pty ltd/DigitalVision; Caroline Purser/DigitalVision; dodo4466/DigitalVision Vectors; Westend61; kali9/E+; Hero Images; Manuel Breva Colmeiro/Moment; SU.2: studiolaut/istock/Getty Images Plus; pbombaert/Moment; immrchris/istock/Getty Images Plus; Justin Lambert/DigitalVision; Vostok/Moment; YinYang/istock/Getty Images Plus; Dstarky/istock/Getty Images Plus; Westend61; Compassionate Eye Foundation/Rob Daly/OJO Images Ltd/DigitalVision; Tim Hall/Cultura; MachineHeadz/istock/Getty Images Plus; U1.2: Emelyn Cabacungan Wong/EyeEm; dangrytsku/istock/Getty Images Plus; Jose Luis Pelaez Inc/DigitalVision; golero/E+; EHStock/istock/Getty Images Plus; Hill Street Studios/DigitalVision; U1.3: Flashpop/DigitalVision; guruXOOX/istock/Getty Images Plus; Westend61; U2.2: belterz/E+; underworld111/istock/Getty Images Plus; volschenkh/E+; Musat/istock/Getty Images Plus; Chiara Benelli/Moment; Sacnicté Montserrat Caballero Vázquez/EyeEm; jackmalipan/istock/Getty Images Plus; Imladris01/istock Editorial/Getty Images Plus; Guido Mieth/DigitalVision; FitchyImages/istock/Getty Images Plus; U2.3: Lorado/E+; drmakkoy/DigitalVision Vectors; Alisovna/istock/Getty Images Plus; Nastasic/DigitalVision Vectors; Brian Ejlertsen/EyeEm; TonyBaggett/istock/Getty Images Plus; Thomas Pollin/Moment; Easy_Asa/istock/Getty Images Plus; gwycech/istock/Getty Images Plus; Bernd Schwabedissen/EyeEm; Chlo Boulos/EyeEm; Hannes Eichinger/EyeEm; U4.2: Larry Busacca/PW18; strmko/E+; bokan76/istock/Getty Images Plus; oneinchpunch/istock/Getty Images Plus; tdub_video/E+; Sally Anscombe/DigitalVision; Imgorthand/E+; U4.3: MoniqueRodriguez/E+; Stephen Buwert/E+; Richard Villalonundefined undefined/istock/Getty Images Plus; michael1959/istock/Getty Images Plus; Talaj/istock/Getty Images Plus; Robert Nicholas/OJO Images; Rawpixel/istock/Getty Images Plus; Hill Street Studios/DigitalVision; Hero Images; SrdjanPav/E+; Frederick Bass; John Lund/Stockbyte; Pal Szilagyi Palko/EyeEm; U5.2: Arcaid Images; Louis Turner/Cultura; svetikd/E+; JTPalacio/Moment; Fotosearch; Johner Images; Eoneren/istock/Getty Images Plus; BY MATTHEW HEPTINSTALL/Moment; Lilly Bloom/Cultura; valzhina/istock/Getty Images Plus; U5.3: Alfadanz/istock/Getty Images Plus; grimgram/istock/Getty Images Plus; adekvat/istock/Getty Images Plus; Juanmonino/E+; Anastasiia_M/istock/Getty Images Plus; Adie Bush/Cultura; ELIKA/istock/Getty Images Plus; Indeed; Angel_1978/istock/Getty Images Plus; Yapanda/istock/Getty Images Plus; Vadim_Ermak/istock/Getty Images Plus; kimberrywood/DigitalVision Vectors; U6.2: wilpunt/istock/Getty Images Plus; Daniela968/istock/Getty Images Plus; Priyanshi Shahi/EyeEm; no_limit_pictures/istock/Getty Images Plus; Marc Debnam/Photodisc; SchulteProductions/E+; vm/E+; skynesher/E+; courtneyk/istock/Getty Images Plus; TommL/E+; U6.3: Enrique Díaz/7cero/Moment; Andrey Danilovich/E+; kokouu/E+; Adam Gault/OJO Images; Olexii/istock/Getty Images Plus; Oleh Slobodeniuk/Moment; Dougal Waters/DigitalVision; wissanu01/istock/Getty Images Plus; fotostorm/istock/Getty Images Plus; diane555/DigitalVision Vectors; ugurhan/E+; U7.2: Enis Aksoy/DigitalVision Vectors; Vectorios2016/DigitalVision Vectors; mrs/Moment; Tomasz Zajda/EyeEm; Phoenixns/istock/Getty Images Plus; skynesher/E+; U7.3: Vuk Ostojic/Moment; bjones27/E+; nicoletaionescu/istock/Getty Images Plus; michaeljung/istock/Getty Images Plus; cenkerdem/DigitalVision Vectors; BraunS/E+; MediaProduction/E+; ER Productions Limited/DigitalVision; Sergey Peterman/istock/Getty Images Plus; U8.2: yuoak/DigitalVision Vectors; Dstarky/istock/Getty Images Plus; ninglu/istock/Getty Images Plus; Ateli/istock/Getty Images Plus; pop_jop/DigitalVision Vectors; SeanPavonePhoto/istock Editorial/Getty Images Plus; Richard Newstead/Moment; Steve Mason/Valueline; VladimirFLoyd/istock/Getty Images Plus; Fuse/Corbis; kali9/E+; U8.3: Robyn Breen Shinn/Image Source; Zero Creatives/Image Source; Hillary Kladke/Moment; John M Lund Photography Inc/DigitalVision; Steve Baccon/DigitalVision; stevecoleimages/E+; Gogiya/istock/Getty Images Plus; jrubacha/istock/Getty Images Plus; U9.2: GoodLifeStudio/istock/Getty Images Plus; PeopleImages/E+; ViewApart/istock/Getty Images Plus; Betsie Van Der Meer/DigitalVision; Judith Burrows/Hulton Archive; Hill Street Studios/DigitalVision; Aleksander Rubtsov; Hello Lovely; Satoshi-K/E+; recep-bg/E+; U9.3: kali9/istock/Getty Images Plus; Johanna Lindberg/EyeEm; atbaei/E+; Klaus Mellenthin/; Molly Aaker/Moment; fergregory/istock/Getty Images Plus; LeslieLauren/istock/Getty Images Plus.

Video
All video clips are sourced from Getty Images.

SU1: focusimage/Image Bank Film; Counter/Image Bank Film; AzmanL/Creatas Video; Eternity In An Instant/Image Bank Film: Signature; Motortion/Creatas Video+; U1.2: aleksandarnakovski/Creatas Video+; U1.3: TheRadarLab/Creatas Video+; U2.2: footagefactory/Image Bank Film; ITN; ImagesBazaar/Photolibrary Video; zefart/Creatas Video+; U3.2: Freezelight/Creatas Video; Serhii Brovko/Creatas Video+; Robert Harding Video/Photolibrary Video; Stereo Lab Films/Image Bank Film; Gal Productions/Image Bank Film; CaiaFilmJV/Creatas Video; Aynur karanis Creatas Video+/Getty Images Plus; U3.3: Pixelchrome Inc/DigitalVision; Monica Garcia/Moment; Pixelchrome Inc/DigitalVision; Sky News/Film Image Partner; danr13/Creatas Video+; asiseeit/Vetta; Rolf Sjogren/Image Bank Film: Signature; U4.2: selamiozalp/Creatas Video; PawelRut/Creatas Video+; Allstar Picture Library/Photolibrary Video; alisbalb/Creatas Video+; vitanovski/Creatas Video+; U6.3: SrdjanPav/Creatas Video; Kelly Mason/Image Bank Film; Erik Van Ingen/Image Bank Film; U8.3: AlexLMX/Creatas Video+; U9.2: kali9/Creatas Video; Filomedia/Creatas Video+; andresr/Vetta; slavemotion/Creatas Video.

Audio
The following audio clip is sourced from Getty Images.

SU1: Laurynas Poskus/SoundExpress

Video produced by Lucentum Digital

Everyday English

Photography
All photographs are sourced from Getty Images.

U1.4: Hero Images; Westend61; Olga KashurinaiStock/Getty Images Plus; RichLegg/E+; linearcurves/DigitalVision Vectors; Caiaimage/Robert Daly; Karunyapas Krueklad/EyeEm; calvindexter/DigitalVision Vectors; U2.4: PeopleImages/E+; Hero Images; Anu Mendes/EyeEm; Jean-Luc Rollier/EyeEm; Jon Paul Perry arranginglight.com/Moment; Rudy Orozco/EyeEm; Jim Zuckerman/Corbis; calvindexter/DigitalVision Vectors; Glowimages; U3.4: Christina Reid/EyeEm; Anu Mendes/EyeEm; Paolo De Santis/EyeEm; Johner Images; HRAUN/E+; rusm/E+; U4.4: Robert Nicholas/OJO Images; Passakorn Leelawat/EyeEm; Waitforlight/Moment; Westend61; KTSDESIGN/Science Photo Library; Danielle Kiemel/Moment; calvindexter/DigitalVision Vectors; U5.4: Hero Images; Sunwoo Jung/DigitalVision; Adam Crowley; oxygen/Moment; dlinca/iStock/Getty Images Plus; Alex Wilson/Photodisc; danilovi/E+; imagenavi; calvindexter/DigitalVision Vectors; U6.4: Zhou Jiang/Moment; nico_blue/DigitalVision Vectors; Colors Hunter - Chasseur de Couleurs/Moment; Peter Pesta Photography/Moment; Erik Isakson; John Fedele; Chris Collins/Corbis/Getty Images Plus; Westend61; U7.4: ExperienceInteriors/E+; Vostok/Moment Open; Felix Kayser/EyeEm; meshaphoto/E+; Sebastian Arning/EyeEm; U8.4: Bulgac/E+; Jay's photo/Moment; enjoynz/DigitalVision Vectors; imaginima/E+; Hero Images; gawrav/E+; elwisz/E+; Westend61; Guerilla; DebraLee Wiseberg/E+; calvindexter/DigitalVision Vectors; U9.4: ExperienceInteriors/E+; Hero Images; Aliaksandr Bukatsich/iStock/Getty Images Plus; Manuel Breva Colmeiro/Moment; PeopleImages/E+; BSPC/Creatas Video; KatarzynaBialasiewicz/iStock/Getty Images Plus; imaginima/E+; linearcurves/DigitalVision Vectors.

Video
All video clips are sourced from Getty Images.

U3.4: selamiozalp/Creatas Video; U4.4: Nino Film GmbH/Moment Video RF; Warner Bros. Studios/Warner Bros. Entertainment.

Audio
All audio clips are sourced from Getty Images.

U1.4: Maximiliano Silveira/SoundExpress; Ian Hubball/Sound Effects by Getty Images; Larry Bryant/Sound Effects by Getty Images; U2.4: Maximiliano Silveira/SoundExpress; Igor Arhipov/SoundExpress; Tunart/Sound Effects by Getty Images; U3.4: Maximiliano Silveira/SoundExpress; U4.4: Maximiliano Silveira/SoundExpress; U5.4: Maximiliano Silveira/SoundExpress; U6.4: Maximiliano Silveira/SoundExpress; U7.4: Maximiliano Silveira/SoundExpress; U8.4: john solo sensations/Sound Effects by Getty Images; Jonny Slatter/Sound Effects by Getty Images; U9.4: Maximiliano Silveira/SoundExpress; Jeremy Mayes/Sound Effects by Getty Images.

Video produced by Lucentum Digital.

Illustrations
Jose Rubio and Antonio Cuesta

Audio Produced by Creative Listening

Typeset by QBS Learning

Authoring
Vicki Anderson, Ingrid Wisniewska and Philip Wood

Freelance editorial work

Diana Anyakwo, Inés Avello, Charlotte Johnson, Dan Morris, Mathew Rust, Melissa Wilson and Pen and Ink Book