According to the passage, the aging process is a struggle between
A．destruction and repair.
B．damage and control.
C．control and reverse.
D．repair and reverse.

判断题护面墙除承受自重外，不能承受墙背土压力。()

未分类题The author uses the result of Gallup poll to argue thatA．the first ladies in America are respected by the whole nation.B．Rosalynn is not as good as Nancy Reagan in the 1980s.C．Gallup poll is an effective organization to collect public opinions.D．today's famous people are created for their well-knowness.

判断题励磁绕组断线的他励直流电动机，额定负载起动时，将出现电流过大情况。()

未分类题The phrase 'putting their heads together'(Lines 7-8, Paragraph 3)meansA．making efforts collectively.B．always getting together.C．thinking in the same way.D．chatting together.

判断题三相异步电动机根据转子结构的不同，分为笼型异步电动机和绕线型异步电动机。()