Lesson One 1
Lesson Two 9
Lesson Three 15
Lesson Four 24
Revision Exercises(Lesson One～Four) 30
Lesson Five 33
Lesson Six 39
Lesson Seven 46
Lesson Eight 54
Revision Exercises(Lesson Five～Eight) 61
Lesson Nine 64
Lesson Ten 72
Lesson Eleven 81
Lesson Twelve 89
Revision Exercises(Lesson Nine～Twelve) 97
Key to Comprehensive Exercises综合练习答案 100
Supplementary Reading补充读物 102