Elementary

• Oxford English Grammar Course. With key. Michael Swan and Katherine Walter.
• Essential Grammar in Use with Key. Raymond Murphy.
• Practice Grammar with Answers. Oxford University Press.
• Grammar in View 1, Milada Broukal, McGrawHill.
• English Vocabulary in Use Pre-Intermediate (with answers) by Stuart Redman. Cambridge University Press
• Test your vocabulary 1 – Watcyn-Jones, P. Penguin.

Intermediate

• Oxford English Grammar Course:.Intermediate..Michael Swan. Catherine Walter
• English Grammar in Use with Answers. Murphy. Cambridge University Press
• Grammar Practice for Intermediate Students. Elaine Walker. Longman.
• Oxford-Practice Grammar. New edition (with answers) Eastwood
• English Vocabulary in Use: Pre-Intermediate and Intermediate (with answers) Redman. Cambridge University Press

Advanced

• Advanced Language Practice with Key, Michael Vince with Peter Sunderland. MacMillan
• Advanced Vocabulary in Use, by Michael McCarthy and Felicity O’Dell, C.U.P.
• Advanced Writing with English In Use, Hugh Cory, O.U.P.
• Cambridge Grammar of English, Ronald Carter & Michael McCarthy, Cambridge University Press
• English Collocations in Use, Michael McCarthy and Felicity O’Dell. CUP. Intermediate.
• English Pronunciation in Use (Intermediate), by Mark Hancock, C.U.P.English Pronunciation in Use (Advanced), by Martin Hewings, C.U.P.
• English Vocabulary Organiser, by Chris Gough, Language Teaching Publications.
• Idioms Organiser, Jon Wright, Language Teaching Publications.
• Longman Advanced Learners’ Grammar, by Mark Foley and Diane Hall. Longman.
• Practical English Usage, Michael Swan, O.U.P.

Text Book Online Practice 

• File Elementary
• File Pre-intermediate
• File Intermediate
• File Upper-Intermediate  
• FURTHER ONLINE PRACTICE

Monolingual and Bilingual Dictionaries

https://www.wordreference.com/es/translation.asp

https://www.collinsdictionary.com/

https://dictionary.cambridge.org/

https://www.oxfordlearnersdictionaries.com/

https://www.oxfordlearnersdictionaries.com/topic/

https://dictionary.cambridge.org/plus/quiz/image/

Newspapers

https://www.theguardian.com/europe

https://www.thetimes.co.uk/

https://www.washingtonpost.com/

https://eu.usatoday.com/

https://www.wsj.com/

https://www.economist.com/

Learn English (British Council)

https://learnenglish.britishcouncil.org/

https://learnenglishteens.britishcouncil.org/

Language Exchange

https://www.conversationexchange.com/

https://language.exchange/

https://www.esmadrid.com/en/language-exchange-venues