21.It was not until he arrived in class

网友回答

这个有问题,
我觉得是It was not until he arrived in class did he realized that he had
forgotten his book.
======以下答案可供参考======
供参考答案1:
题抄错了吧供参考答案2:
that he
供参考答案3:
同学，选项呢。。。后面应该用倒装
供参考答案4:
that强调句啊！！
供参考答案5:
是强调句型，不过你的句子写错了。应该是：It was not until he arrived in class that he realized he had forgotten his book.
供参考答案6:
这句话可以说成
not until he arrived in class did he realized ....
如果要是强调句 即去掉it is 和and 句子意思仍然完整
故为 it was not until he arrived in clss that he realized.....