33. Daisy said that Peter had better learn harder for the final exam

34.Ba has never gone to HCMC

35.Despite being a poor student, Tom learns very well

36.Singapore is said to be green and clean

37.The only thing which makes me worried is how to___

38.The water in this lake is too dirty to swim in

39.Mary couldn't go to school yesterday because of her sickness

40.Thank you very much for your helping me with the work.

1.D

2.B had seen it with his own eyes

3.D

4.A Janet asked us where we had been spending our holidays

5.B no one could recognize him

33, Daisy said Peter had better learn harder for the final exam

34, Ba has never gone to Ho Chi Minh City

35, Despite being a poor student,Tom learns very well

36, Singapore is said to be green and clean

37, The only thing which makes me worried is how to go home

38, The water in this lake is too dirty to swim in

39, Mary couldn't go to school yesterday because of her sickness

40, Thank you very much for helping me with the work.

1, C

2, B

3, D

4, A 

5, B 

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