知识点总结
概念：为了强调句子的某一成分（通常是主语、宾语、或状语），常用强调句型。
构成：It is (was) +被强调部分+that(who)…；强调的主语如果是人，that和who都可用。如：
Last night I saw a film in the Youth Palace.
强调主语：It was I that (or who) saw a film in the Youth Palace last night.
强调宾语：It was a film that I saw in the Youth Palace last night.
强调地点状语：It was in the Youth Palace that I saw a film last night.
强调时间状语：It was last night that I saw a film in the Youth Palace.
另外，还要注意下面几点：
1）在强调主语时，that 后的谓语动词要与被强调者保持人称和数的一致。如：
It is I who am a teacher.
2）即使被强调的主语是复数，主句中的谓语动词也用单数。如：
It is they who often help me with my lessons.
3）在强调时间、地点、原因或方式状语时，不能用when，where，why或 how ，而要用that 。如：
It was only when I reread his poems recently that I began to appreciate their beauty.
It was in the house that the murder happened.
It was because her mother was ill that she didn't go with us.
4强调句型：It is(was) not until ...that... 注意此时从句中的谓语动词要用肯定式。如：
It was not until 12 o'clock last night that my father came home.
It was not until she took off her dark glasses that I realized she was a famous film star.
5）原句的谓语动词如果是现在或将来的各种时态，用It is…that (who)…；如果原句谓语动词是过去各种时态，则用It was… that(who)…
6）在强调一般疑问句中的某一成分时，主句要用一般疑问句的语序。that后面的原句其余部分在移走了被强调部分后词序及词形都不可以改动。如：
Did this happen in Beijing?
Was it in Beijing that this happened?
7）特殊疑问句中只有疑问词可以强调，其强调结构是“疑问词+is (was) it that...? " 如：
Where were you born?
Where was it that you were born?
8）强调句型容易和句型It is/was+名词+that名词从句混淆。如果把构成强调句型结构的词It is (was) … that(who)… 去掉，被强调部分归位后，应该能够形成一个完整 的句子（这也是判断是否是强调句型的方法）。但后者的It is/was…that 是不可去掉的，否则that前的名词就找不到位置，原句也不再成立，如下面这个句子如去掉It is/was…that就不再完整：
It was the rule of the school that the pupils should wear their school uniforms.
强调句型还容易跟It is/was+形容词+that名词从句这一句型混淆。如：It is clear (obvious, true, possible, certain....) that ..... 该句型中it 是形式主语，真正的主语是that 引导的主语从句，常译为”清楚(显然, 真的, 肯定…)”是主语从句最常见的一种结构。
It is very clear that he’s round and tall like a tree.
That he’s round and tall like a tree is very clear.
9)强调句可以用作宾语从句。如：
He told me that it was because he was late for class that he was punished.
I really can’t remember where it was that I first met the man.
10）强调句型可有如下变体：It is/was变成“情态动词+be”。如：
It may be my bike that he is riding.
It must have been the manager that spoke to you.
11）与疑问词连用构成特殊疑问句和感叹句。如：
Whom was it that Mr. Smith saw in the park yesterday?
Why is it that silver is not widely used as a conductor?
What a beautiful picture it is that you have drawn!
12）被强调的名词或代词可带有一个定语从句。如：
Was it Bill, who plays football well, that helped the blind man cross the road?
It was in the school, where（or：in which） I once studied, that we hold a party.
Was it in the house, which we visited last year, that the murder happened?
误区提醒
1.不能确定是否强调句；2.强调部分后用when或where，不用that;3.疑问语序不熟悉犯错；4.受各种从句干扰出错。
【典型例题】
1）.It was from only a few supplies that she had bought in the village _______ the hostess cooked such a nice dinner.
A. where B. that C. when D. which
解析：迷惑点在于强调部分中含有一个定语从句that she had bought in the village。答案：B.
2）. John's success has nothing to do with good luck. It is years of hard work has made him what he is today.
A. why B. when C. which D. that
解析：答案：D。题干为强调句型，被强调部分为主语部分years of hard work，故选D项
3). It was _____ he came back from Africa that year _________ he met the girl he would like to marry.
A. when; then B. not; until C. not until; that D. only; when
解析: 含not… until…的强调句型。根据It is ……that 结构可知,答案 C。此题中的that为干扰因素。
