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Lesson 20 1
Lesson 21 8
Lesson 22 17
Lesson 23 (Revision) 25
Lesson 24 32
Lesson 25 42
Lesson 26 51
Lesson 27(Revision) 62
Lesson 28 70
Lesson 29 79
Lesson 30 92
Lesson 31 102
Lesson 32(Revision) 113
Vocabulary 124