第13题: [单项选择]He left early on the ______ that he had a bad toothache and had to see the dentist. A. prescription B. pretext C. knowledge D. precondition 参考答案:B 答案解析:[精解] 题型:词汇题。on the pretext that以……为托辞,on the prescription that根据……指示, on the knowledge that得知……,on t
第14题:[多选题]对同步发电机的并列操作有(____)基本要求。 A.并列瞬间,发电机的冲击电流不应超过规定的允许值
B.并列瞬间,发电机应无冲击电流
C.并列后,发电机应能迅速进入同步运行
D. 并列后,发电机的暂态过程要长
参考答案:AC