问题
Only after spending several nights working on the math problem to wonder whether the problem was wrongly set.
A:had he begun
B:he began
C:did he begin
D:began he
B:he began
C:did he begin
D:began he
正确答案是：
同类题型
It is ___ the customers’ needs that hasmade chain stores so popular in big cities in China
It’s bad news that quite a few rare animals are _____ each other. [ ]
She’s already left for Nanjing, — Yes, she is in Nanjing now.
So you missed the meeting—____ I got there ten minutes before itfinished