39. _____ men have learned much from the behavior of animals is brand-new.
A. That
B. Those
C. What
D. Whether
40. A man escaped from the prison last night. It was a long time ____ the guards discovered what had happened.
A. before
B. until
C. since
D. when
41. Government cannot operate effectively ____ it is free from such interference.
A. so long as
B. so that
C. unless
D. because
42. No matter how frequently ____, the works of Beethoven always attract large audiences.
A. performing
B. performed
C. to be performed
D. being performed
43. ____ quit recently, most mothers in Britain did not take paid work outside the home.
A. Before
B. Until
C From
D. Since
44. In some countries, ____ is called “equality” does not really mean equal rights for all people.
A. which
B. what
C. that
D. one
45. Liquids are like solids ____ they have a definite volume.
A. in that
B. for that
C. with that
D. at that
参考答案:
39.A 40.C 41.C
42.b No matter how引导的是让步状语从句，其主语the works和助动词are被省略。
43.B 44.B 45.A
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