C. until D. if
46. ______ there is a snowstorm or some other bad weather, the mail always comes on time.
(2007上海春)
A. Because B. If
C. When D. Unless
47. My parents live in a small village. They always keep candles in the house ______ there is a
power cut.（2007-重庆）
A. if B. unless
C. in case D. so that
48. The field research will take Joan and Paul about five months; it will be a long time _____ we
meet them again.（2007-安徽）
A. after B. before
C. since D. when
49. Many of them turned a deaf ear to his advice, _____ they knew it to be valuable.（2007-浙江）
A. as if B. now that
C. even though D. so that
50. ____ you have tried it, you can’t imagine how pleasant it is.（2006-北京）
A. Unless B. Because
C. Although D. When
51. If you are traveling the customs are really foreign to your own, please do as the
Romans do.（2006-天津）
A. in which B. what
C. when D. where
52. ____ he has limited technical knowledge, the old worker has a lot of experience.（2006-全国I）
A. Since B. Unless
C. As D. Although
53. In peace, too, the Red Cross is expected to send help _____ there is human suffering.（2006-
江西）
A. whoever B. however
C. whatever D. wherever
54. How can you expect to learn anything ____ you never listen?（2006-山东）
A. in case B. even if
C. unless D. when
55. ---- How long do you think it will be ______ China sends a manned spaceship to the moon?
---- Perhaps two or three years. （2006-福建）
A. when B. until
C. that D. before
56. Much of the power of the trade unions has been lost. be very great.（2006-广东）
A. As a result B. As usual
C. Even so D. So far
57. "You can't have this football back man said firmly.（2006-广东）
A. because B. since
C. when D. until