逆变式高压发生器常用的整流方式是 （）
A.自整流
B.单相全波
C.三相六波
D.倍压整流
E.三相十二波
参考答案：D
When I said that someone was late for the meeting, I ______ you. Why were you so angry at that time? [ ]
A. didn't refer to
B. wasn't referring to
C. haven't referred to
D. hadn't referred to
海德格尔追寻存在意义的踪迹是“（）”。
