问题补充：
It we had stayed together for a couple of weeks I found we had a lot in common.
A. was until; when
B. was until; that
C. was not until; when
D. was not until; that
答案：
A. was until; when
B. was until; that
C. was not until; when
(答案→)D. was not until; that
解析：句意：直到我们呆在一起几个星期，我才发现我们有很多相同之处。这里使用的是：It was...that...构成强调句，对not until we had stayed together for a couple of weeks进行强调。在这种强调句式中，一般用that引出句子的其他部分。如果被强调的部分是表示人的意义的名词时，可以用who代替that引出句子的其他部分；所以选D。
