51.It is essential that he（ ）all the facts first.

64.He asked me to lend him some money, which I agreed to do,（ ）that he paid me back the following week.

63.（ ） you（ ）further problems with your printer, contact your dealer for advice.

62.The meeting was put off because we（ ）a meeting without John.

61.What’s the chance of（ ）a general election this year?

60.That was not the first time he（ ）us. I think it’s high time we（ ）strong actions against him.

59.Do you know Tim’s brother? He is（ ）than Tim.

58.I know he failed his last test, but really he’s（ ）stupid.

57.I went there in 1984, and that was the only occasion when I（ ）the journey in exactly two days.

56.Because fuel supplies are finite and many people are wasteful, we will have toinstall（ ）solar heating device in our home.

55.（ ）conscious of my moral obligations as a citizen.