It was not until Susan came back her close friends were waiting for him.
A. which she knew
B. which did she know
C. that she knew
D. that did she know
网友回答
A. which she knew
B. which did she know
(答案→)C. that she knew
D. that did she know
解析： 考查强调句：It was not until…that….，句意：直到苏珊回来她才知道她的亲密的朋友在等着她。注意that后面的句子不用倒装，因为这里not until不是放在句首的，选C。