244.When you have finished with that book, don’t forget to put it back on the shelf, ______ ?

59.__________ at in this way, the present economic situation doesn't seem so gloomy.

58.Firms that use computers have found that the number of staff __________ is needed for quality control can be substantially reduced.

57.All of us would have enjoyed the party much more if there __________ quite such a crowd of people there.

56.You __________ Jim anything about it. It was none of his business.

55.I was very much put __________ by Mark's rude behavior; it really annoyed me.

54.My mother can't get __________ because she has rheumatism(风湿病).

53.There __________ nothing more for discussion, the meeting came to an end half an hour earlier.

52.Do help yourself to some fruit,__________ you?

51.The central provinces have floods in some years, and __________.

50.This is an illness that can result in total blindness __________ left untreated.