Unit 1 Articles and Nouns Unit 2 Countable / Uncountable Nouns and Quantifiers Unit 3 Partitives Unit 4 Reflexive and Indefinite Pronouns Unit 5 Possessives and Whose Unit 6 Sentence Parts : Subject, Verb, and Complement Unit 7 Sentence Patterns Unit 8 Comparatives : Adjectives and Adverbs Unit 9 Superlatives : Adjectives and Adverbs Unit 10 The Present Simple Tense Unit 11 The Present Continuous Tense Unit 12 The Future Simple Tense Unit 13 The Past Simple Tense Unit 14 The Past Continuous Tense Unit 15 The Past Tense with When / While Unit 16 Gerunds Unit 17 Infinitives Unit 18 Prepositions Unit 19 Coordinating Conjunctions Unit 20 Subordinating Conjunctions Answer Key