33. The trees must _______ three times a week.

　　　 A. water　　　　　 B. is watering　　　 C. be watered　　　 D. waters

32. _______ me carefully, boys and girls. Can you _______ me?

　　　　 A. Listen to; hear　 B. Hear; listen to　 C. Hear; hear　　 D. Listen to; hear from

31. His uncle _______ in three days.

　　　　 A. returns　　　 B. has returned　　 C. returned　　　　 D. will return

30. We must do something to stop people from _______.

　 A. to throw litter about 　B. to throw litter intoC. throwing litter about D. throwing litter into

29. Every spring, many trees _______ along the river.

　　　　 A. were planted　　 B. is planted　　　　 C. will be planted　　 D. are planted

28. . –Did you see Tom at the party?　 -- No, he ______ by the time I got there.

　　　 A. left　　　 B. was leaving　　 C. had left　　　 　D. has left

27. Yuki loves wearing strange hats because she wants people to _______ her.

　　　　 A. believe　　　　　 B. control　　　　　 C. notice　　　　　 D. visit

26. If Mary _______ next Sunday, we will go boating together.

　　　　 A. will come　　 　B. comes　　 　C. shall come　　 　　D. should come

25. Would you _______ your voice a little so that everyone can hear you?

　　　　 A. rise　　　　　　 B. put　　　　　　　 C. lift　　　　　 D. raise

24. Don’t make so much noise. We _______ to the music.

　 　　A. listened　　　　 B. listen　　　　　 C. are listening　　 D. have listened