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