[单选题]1.It was the third time _____ he had done this experiment.A.since B.before C.which D.that
问题描述：
[单选题]1.It was the third time _____ he had done this experiment.
A.since
B.before
C.which
D.that
答
选D.是定语从句。
句型：It is the + 序数词\ only + that +主语+ 现在完成时；
It was the + 序数词\only + that +主语+ 过去完成时。
答
D
强调句型