152.Modern plastics can very high and very low temperatures.

48.If Ibetter at science, I＇d be a doctor now.

47.If they hadn＇ t spent all the money on the stocks, their lifeso miserable at the moment.

46.Had she worked harder, shethe exams.

45.My mother suggests that wefor a change this weekend.

44.He talks so much about America as if hethere before, but he has never been abroad.

43.Without water and sunshine, plants on the earthat all.

42.I didn＇t attend the lecture because I was sick, but I wish Ithere.

41.I, d just as soonthose important papers with you.

40.finish his homework, he would have come to class.

39.It is requested that the rent for the housein advance.