A. 1977年 B. 1978年 C. 1979年 D. 1980年
A. NPN型Si管 B. NPN型Ge管 C. PNP型Si管 D. PNP型Ge管
A. 论语 B. 孟子 C. 庄子 D. 国语
A. has died B. died C. is died D. has been died
A. differently B. partially C. respectively D. equally
A. opened B. open C. opening D. openly
A. tens of thousands 2000 B. about ten of thousands C. about three thousands D. about three thousand
A. did I B. had I C. I had D. I did
A. three dozen of B. three dozen C. three dozens D. three dozens of
A. most preference B. preferencer C. preference D. preferencest
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