直接耦合放大电路只能放大直流括号，不能放大交流信号。
查看答案
直接耦合放大电路的温漂很小，所以应用很广泛。
A. 对
B. 错
There are_______ people here.
A. three hundred and twenty-one
B. three hundreds and twenty-one
C. three hundred, twenty one
D. three hundreds, twenty and one
_______ people are seeing the movie now.
A. Five hundred
B. Five hundreds of
C. Hundreds of
D. Hundred of
His mother is in _________
A. her forty
B. her the forty
C. her forties
D. her fortieth
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