问题
our US visa—Not yet. I toobusy to apply for an appointment, so I didn’t go to Shanghai last week
A:was
B:have been
C:had been
D:would be
B:have been
C:had been
D:would be
正确答案是：
同类题型
Not until World War II ______ to use new chemicaltechniques to purify penicillin.
Tom spent his childhood in England . Is it true? — No. It was in China ______he spent his childhood.
What can we students do _____ the environment
Before a problem can be solved，it must be obvious____the problem itself is.
It was so dark in the cinema that I could hardly ______ my friend.