Exercise 1 1
Exercise 2 8
Exercise 3 14
Exercise 4 20
Exercise 5 26
Exercise 6 32
Exercise 7 38
Exercise 8（Test One） 44
Exercise 9 51
Exercise 10 58
Exercise 11 64
Exercise 12 71
Exercise 13 79
Exercise 14 85
Exercise 15（Test Two） 91
Key to Book 3 101