解析：it is⼀was + 被强调部分 + that 从句

强调句型：It +is/was +被强调部分+that/who-从句

英语常用的强调结构是"It is (was)+被强调部分(主语、宾语或状语)+who
(that)..."。一般说来,被强调部分指人时,用who;指事物时用that,但that也可以指人。在美国英语中指事物时常用which来代替that。

1. 陈述句的强调句型

It is/ was + 被强调部分（通常是主语、宾语或状语）+ that/ who（当强调主语且主语指人）+ 其他部分。

例子 It was yesterday that he met Li Ping.

2. 一般疑问句的强调句型

同上，只是把is/ was提到it前面。

例子 Was it yesterday that he met Li Ping?

3. 特殊疑问句的强调句型

被强调部分（通常是疑问代词或疑问副词）+ is/ was + it + that/ who + 其他部分？

例子 When and where was it that you were born?

4.not … until … 句型的强调句

A. 句型为：It is/ was not until + 被强调部分 + that + 其他部分

普通句：He didn't go to bed until/ till his wife came back.

强调句：It was not until his wife came back that he went to bed.

B. 注意：

此句型只用until，不用till。但如果不是强调句型，till, until可通用；因为句型中It
is/ was not ... 已经是否定句了，that后面的从句要用肯定句，切勿再用否定句了。

5.谓语动词的强调

A.
It is/ was ... that ... 结构不能强调谓语，如果需要强调谓语时，用助动词do/ does或did

Do sit down. 务必请坐。

Do be careful when you cross the street. 过马路时，务必（千万）要小心啊！

B. 注意：

此种强调只用do/ does和did，没有别的形式；过去时用did，后面的谓语动词用原形。

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