It做形式主语讲解PPT学习教案

1、会计学1 It做形式主语讲解做形式主语讲解 Its necessary for the young to master two foreign language. Its a waste of time talking to her any more. Its a pity that you missed the exciting football match. 动词不定式动词不定式 动名词动名词 从从 句句 形式主语 第1页/共13页 It 作为作为形式主语形式主语的用法的用法 当当 不定式、动名词、从句不定式、动名词、从句 等用作等用作 句子主语时，为保持句子平衡，句子主语时，为保持句子平

2、衡， 通常把真正的主语放在句末，而通常把真正的主语放在句末，而 在句首使用形式主语在句首使用形式主语it. 第2页/共13页 拒绝是令人遗憾的拒绝是令人遗憾的. 记住这一点是很重要的记住这一点是很重要的. Its a pity to refuse. Its very improtant to remember this 一、代替动词不定式做形式主语 第3页/共13页 It +be +adj.+（for sb.）to do sth. 此处adj. 通常为描述事件事件的形容词：easy， difficult，hard，necessary，impossible， important，natural,

3、 likely，obvious，useful， useless，dangerous做某事是 Its necessary for us to master a foreign language. 第4页/共13页 第5页/共13页 It + be +名词词组+动词不定式 eg. It is not a good habit to stay up too late. 常见句型： It takes/took sb. some time/money to do sth. 第6页/共13页 It is no good crying over spilt milk. It is no use castin

4、g pearls before swine . 覆水难收覆水难收 不要明珠暗投，对牛弹琴不要明珠暗投，对牛弹琴 构成如下结构：构成如下结构： It is +no use/no good/not any good/not any use+ doing sth. 二、代替动名词作形式主语 第7页/共13页 It + be + 名词词组 + 主语从句 这类名词有：a fact, a pity, a shame, an honour， a question，a surprise，common knowledge eg.Its common knowledge that people cannt liv

5、e without water . 三、代替从句做形式主语 It + 不及物动词 + that（as if）-从句 这类不及物动词有：look，seem，appear， happen，occur eg.It seems that he does not tell the truth. 第8页/共13页 It + be +adj.+that-从句 第9页/共13页 It + be +-ed（过去分词）+ that-从句 It is said that 据说 It is reported that 据报道 It is supposed that 据推测 It is hoped that 希望 It is well known that 众所周知 It is generally considered that普遍认 为 It is suggested that 有人建议 第10页/共13页 练习：把下列格局转换为it做形式主语的句子 1.He was rude to say so. 2.Trying again is of use. 3.When and where to hold the party hasnt been decided. It was rude of him to say so. It is of use trying ag