31. Stop talking or you won’t understand the lesson.

A. If you don’t stop talking, you won’t understand the lesson.

B. If you don’t stop talking, you wouldn’t understand the lesson.

C. If you hadn’t stopped talking, you wouldn’t understand the lesson.

D. If you hadn’t stopped talking, you wouldn’t have understood the lesson.

32. Peter likes going on a picnic with his best friends at weekends.

A. Peter enjoy going on a picnic with his best friends at weekends.

B. Peter enjoys going on a picnic with his best friends at weekends.

C. Peter enjoys go on a picnic with his best friends at weekends.

D. Peter enjoys to go on a picnic with his best friends at weekends.

33. We started to donate money for the poor two years ago.

A. We have donated money for the poor two years ago.

B. We have donated money for the poor for two years.

C. We have donated money for the poor since two years.

D. We have started to donate money for the poor for two years.

34. It’s a good idea to do exercise regularly.

A. You should do exercise regularly.

B. You don’t have do exercise regularly.

C. You will do exercise regularly.

D. You should to do exercise regularly.

35. It takes me three hours to make this model.

A. I spent three hours to make this model.

B. I spent three hours making this model.

C. I spend three hours making this model.

D. I spend three hours to make this model.

36. We decided to stay home and watch TV because It was raining heavily.

A. We decided to stay home and watch TV so It was raining heavily.

B. It was raining heavily, so we decided to stay home and watch TV.

C. It was raining heavily, but we decided to stay home and watch TV.

D. We decided to stay home and watch TV although It was raining heavily.

37. We last ate sea food 2 months ago.

A. We have eaten sea food 2 months ago.

B. We have eaten sea food for 2 months.

C. We haven’t eaten sea food since 2 months.

D. We haven’t eaten sea food for 2 months.