同步触发器在CP=1期间能发生多次翻转，这种现象称为空翻
查看答案
边沿触发器只在时钟脉冲CP上升沿或下降沿时刻接收输入信号，电路状态才发生翻转，从而提高了可靠性。
A. 对
B. 错
主从触发器和边沿触发器的缺点是存在空翻现象。
A. 对
B. 错
She still remermbers the days _____ she spent in the countryside.
A. while
B. that
C. when
D. during which
Helen was much kinder to her youngest child than she was to the others, _____, of course, made the others unhappy.
A. which
B. that
C. what
D. who
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