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51. In the meantime， the question facing business is whether such research is _____ the costs.
A. worth
B. worth of
C. worthy
D. worthwhile
正确答案是
52. In the preface _____ the book， the old scholar attaches great importance to practicalness.
A. to
B. for
C. about
D. of
正确答案是
53. In this experiment， they are wakened several times during the night， and asked to report what they _____.
A. had just been dreaming
B. have just been dreaming
C. are just dreaming
D. had just dreamt
正确答案是
54. In this factory the machines are not regulated ______ but are jointly controlled by a central computer system.
A. independently
B. individually
C. irrespectively
D. irregularly
正确答案是
55. It _____ five years since the famous singer left her hometown.
A. was
B. is
C. has passed
D. had been
正确答案是
56. It is difficult to tell whether a man is angry or not by _____ looking at his face.
A. right
B. barely
C. just
D. hardly
正确答案是
57. It is pretty obvious that more than one person has _____ this affair.
A. laid a hand on
B. had a hand in
C. got the upper hand of
D. got into the hands of
正确答案是
58. It is reported that _____ adopted children want to know who their natural parents are.
A. the most
B. most of
C. most
D. the most of
正确答案是
59. It is strictly _____ that access to confidential documents is denied to all but a few.
A. secured
B. forbidden
C. regulated
D. determined
正确答案是
60. It makes me sick to think of his highly _____ manners.
A. artistic
B. artful
C. artless
D. artificial
正确答案是
51. A 52. A 53. B 54. B
55. B 56. C 57. B 58. C 59. C 60. D