Question

It was when she was about to go to bed ______ the telephone rang.

Answer 1

强调句型，最明显的标志是省略了it is/was… that之后句子仍旧完整。

when she was about to go to bed，  the telephone rang.当她正准备睡觉的时候，电话响了。

这是一个由when引导的时间状语从句+简单句复合而成的复杂句，主句是the telephone rang，时态是一般过去时。

Answer 2

填写 that。

追答

这是一个强调句型，公式是：it is（was）＋被强调部分＋that ＋句子剩余的部分。

本句被强调部分是
状语从句when she was about to go to bed。
还原成不强调句子时：When she was about to go to bed, the telephone rang.

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