17.False
18.True
19.False
20.True
21.C
22.D
23.A
24.B
25.C
26.D
27.D
28.B
29. spoke
30. unidentified
31. accessary
32. embarrassing
33. interesting
34. relationshipper
35. Tourism in many nations plays an important part of the development .
36. He must wash the vegetables carefully if he wants to eat them raw .