It用法及其句型和固定搭配讲解(2)
三、It作主语的句型
1. It takes sb. to do（=sb takesto do）某人用多长时间做某事
例 It took the men a week to mend our roof.（= The men took a week to mend our roof.）
2. It's（just）（un）like sb. to do（不）像某人做某事的风格
例 It was（just）like him to think of helping us.
3. It's（about/high）time that should /v-ed是该做某事的时候了
例 It's（about/high）time that we should take action.
4. It's the x-th time（that） have v-ed第几次做某事了
例 It's the third time that he has failed the driving test.
5. It is/has been since continuous v-ed（延续性动词）某动作已有多长时间不发生了
例 It's 10 years that he lived here
6. It was（not） before过（不）了多长时间某动作发生了
例 It was not long before they arrived.
四、It 作形式宾语
用来替代作宾语的从句、动词不定式、动名词，而把真正作宾语的从句、动词不定式、动名词置于句尾。
It 作形式宾语的常见句型：
1. verb+ it+ adj./noun（for/of）to do/clause （verb=think，believe，suppose，consider，feel，make，keep）
例 I think it hard for you to do the task on your own./I think it hard that you'll do the task on your own.
2. verb+it+adj./noun（one's）doing（adj.=useless/worth/worthwhile）（noun=no use/no good/worth one's while/a waste of time/money/energy/words）（verb=think，believe，suppose，consider，feel，make，keep）
例 I'll make it worth your while telling me about his secret.
3. verb+it+ important/unimportant/necessary/unnecessary/natural/essential that （should）
verb+it+of much/great/no/little importance that（should）
（verb=think，believe，suppose，consider，feel，make，keep）
例 I think it important that you（should）attendthe conference.
4. verb + it+ as+ noun/adj.+ clause（verb=accept，regard，take，see，view）
例 The lecturer takes it as encouraging when so many students attend his lecture.
5. v. +it + prep. + that
owe it to sb. that把归功于
leave it to sb that把留给某人去做
take it for granted that 想当然
keep it in mind that
例 Don't bother to arrange anything. Just leave it to me to sort out.
6. It用在不能直接跟宾语从句的动词后面，尤其是表示好恶的动词后，enjoy，like，love，dislike，resent，hate，don't mind，be fond of，feel like，see to 宾语从句紧跟it之后
例 I hate it you can swim so well and I can't.
7. It用在不能直接跟宾语从句的介词后面，宾语从句紧跟it之后（except that例外）
例 I'm for it that you will follow their advice.
五、强调句型
It is/was+被强调部分+ that（who） 强调句型用来强调谓语动词以外的任何句子成分。当被强调部分是人时也可以用who.
在使用强调句型时需注意以下几点：
1. 请注意强调句型的特殊疑问句
例 When was it that he changed his mind to take part in the activity？
2. 在强调原因状语从句时，只能强调由because所引导的从句
例 It was because he was ill that he didn't come to school yesterday.
3. 在强调not until结构时必须把not与until一起放到被强调的位置上
例 It was not until she took off her dark glasses that I realized she was my brother.
4. 注意强调句型与定语从句的区别
例 It was at 7 o'clock that he came here yesterday.（ 强调句型）
It was 7 o'clock when he came here yesterday.（定语从句）[1][2][3]