Question

19. Tom,   you play the violin so well. But I

you can play the violin.

A. didn't know       B. don't know

C. hadn't known       D. haven't known

Answer 1

19.   A考査动词的时态。句意：汤姆，你的小提琴拉得真好。但是我以前都不知道你会拉小提琴。根据句意作者表达的意思是"以前不知道你会弹钢琴"而现在知道了。所以"不知道"应为过去时态。故选A。