人教高中英语二轮语法回顾与训练---It的用法和there be结构学案（含答案）.docx

高三二轮语法回顾与训练---It的用法和there be结构
1.代词it常用来指代前文提到的事或物，还用在各种特殊句型中。
there be表示“存在”，可用在不同时态和句型中。
2.考点归纳
一、it用法
1. it用作形式主语
（1）It + be + adj. + 主语从句
It is clear（obvious / true / possible / certain…）+ that / whether…从句…
It is essential（important / necessary / right / strange / natural…）+ that从句…（should + 动词原形）
It is uncertain whether he can come to Jenny’s birthday party or not.
It is important that we should learn English well.
（2）It + be + 名词词组 + 主语从句
It’s a pity that you missed the exciting football match.
（3）It + 不及物动词（seem / appear / happen / turn out…等）+ 主语从句 （看来 / 似乎 / 碰巧 / 证明是）
It seemed that he didn’t tell the truth.
It happened that I was out when he called.
（4）It’s + adj. + for / of + sb. + to do sth
特别注意：如何选择介词for 或of？
如果该句型中的形容词是用来说明“某人”的性格或品质（如kind, good, nice, wise, stupid, clever, foolish, silly, impolite, selfish, considerate ...）时，介词用of（“某人”和这些形容词可以构成主系表结构），其它情况介词用for。
It + be + adj. (easy / difficult / hard / important / possible / necessary...) + for sb + to do sth
It + be + adj. (kind / nice / clever / stupid / foolish / silly / impolite / selfish / considerate ...) + of sb + to do / have done sth.
It is unwise of you to give children whatever they want. 孩子需要什么你就给什么是不明智的。
It is necessary for you to turn to your teachers when in trouble. 你遇到困难时求助老师是必要的。
（5）It + be + n. & adj. (no good / no use / useless / senseless / a waste of