—Mike, how about your journey to Mount Huang?—Everything was wonderful except that our car_________ once on the way.
A:broke into
B:broke down
C:turned into
D:turned down
写出近义词。
神奇─____ 赞叹─____ 应有尽有─____ 恋恋不舍─____
一台理想变压器的原、副线圈匝数比为4:1,若原线圈加上u=1000 2 sin100πt V的交流电,则用交流电压表测得副线圈两端的电压是( )
结合材料,运用矛盾主次方面的知识,说明我们应如何正确看待人工智能的发展。