Unit 1: Grammar: Present simple, present continuous, stative verbs
Unit 2: Grammar: Past simple, past continuous, used to
Unit 3: Vocabulary: Fun and games
Unit 4: Grammar: Present perfect simple, present perfect continuous
Unit 5: Grammar: Past perfect simple, past perfect continuous
Unit 6: Vocabulary: Learning and doing
Unit 7: Grammar: Future time (present continuous, will, be going to, present simple)
Unit 8: Grammar: Prepositions of time and place
Unit 9: Vocabulary: Coming and going
Unit 10: Grammar: The passive 1
Unit 11: Grammar: The passive 2
Unit 12: Vocabulary: Friends and relations
Unit 13: Grammar: Countable and uncountable nouns
Unit 14: Grammar: Articles
Unit 15: Vocabulary: Buying and selling
Unit 16: Grammar: Pronouns and possessive determiners
Unit 17: Grammar: Relative clauses
Unit 18: Vocabulary: Inventions and discoveries
Unit 19: Grammar: Modals 1: ability, permission, advice
Unit 20: Grammar: Modals 2: obligation, probability, possibility