问题

I failed in the final examination last term and only then_____ the importance of studies.

A:I realized
B:I had realized
C:had I realized
D:did I realize

正确答案是：

同类题型

He could hardly write his name at the age of 5,________________

atherman said that it is____ to rain, but not _____.

school is very big. And ________is big, too.

With the environment worsening, the government ______ people for more environment protection．

―What do you think made Tom unhappy?―his new bicycle again.