It wasn’t until then their marriage was breaking up because they had little in common.A.

问题补充：

It wasn’t until then their marriage was breaking up because they had little in common.

A. did I realize

B. that I realized

C. had I realize

D. when I realized

答案：

A. did I realize

B. that I realized

C. had I realize

D. when I realized

解析：

这题考查强调句：It is/was not until… that…“直到。。。才”，句意是：直到那个时候他们才意识到因为缺乏共同语言，他们的婚姻快解体了。选B。