主语从句精讲讲义-2025届高三英语上学期一轮复习专项

主语从句 在复合句中，主语为句子的从句叫主语从句，主语从句用陈述语气，句首引导词不能省略。（主语从句的语序：主语在前,谓语在后） 从属连词 不充当成分 That(在句首不能省略) Whether，if(if不能放在句首) 连接代词 在句子中作主语，宾语，表语，定语 Who，whoever，whom，what，whatever，whose，which 连接副词 在句子中作状语 When，where，why，how…… 找出主语从句 1. 找谓语，谓语前的句子就是主语从句 2. It作为形式主语，从句是真正的主语即主语从句 主语从句分类 1. That引导的主语从句，that不作成分，无意义，在句首时不能省略，it作形式主语式that可以省略。 That he will come is certain. It is certain (that) he will come. 2. Whether/if引导的主语从句，在句子中不作成分，无意义，不能省略，在句首只能用whether，并且whether 与or not 连用时，不能用if代替 Whether we'll go camping tomorrow depends on the weather. It depends on the weather whether/if we'll go camping tomorrow. It doesn't matter whether he will come or not。 3. 连接代词who/whom/whose/what/which/whoever/whatever引导的主语从句，在句子中作主语，宾语，表语或者定语，起到连接作用，有实际意义，不可省略。 whatever和whoever引导的主语从句不含疑问意义,相当于名词后加一个定语从句 whoever=anyone who whatever=anything that What you said yesterday was right.你昨天说的是对的 Who will go makes no difference.谁去没有区别 Whatever was said here must be kept secret.无论在这说什么都必需保密 Whoever breaks the law will be punished.无论谁违法都将受惩罚 4. 连接副词when/where/why/how引导的主语从句，作状语成分，起到连接作用，有实际意义，不能省略。 Why he didn't come yesterday is unknown. How this happened is not clear. When he will come is unknown. 5. It 作形式主语，从句时真正的主语时的常用情况 1 It be+名词+that从句 It is a pity/shame that..可惜的是, It is a surprise that... 令人吃惊的是.... It is a pity that lt is a fact that... 事实是. It is common knowledge that……是常识 2 It be+形容词+that从句（obvious, likely, true外，其它通常用虚拟语气即should+动词原形） It is important that... It is possible/likely that... It is obvious/clear that... It is obvious that you are It is true that.... 3 It +be+过去分词+主语从句 It is said that... 据说... It is well-known that众所周知... It is reported that... 据报道... It is believed that ... 人们相信.. It is suggested that+(should) do... 建议.. 4 It+不及物动词+that从句 It happened that...碰巧... It occurred to sb, that...某人突然想到... It appears/seems that...似乎，好像... It happened that l was out yesterday 6. 主语从句的主谓一致 1 单个主语从句作主语时，主句谓语动词用单数 Why he left here was a secret. 2 由两个或多个连接词引导的一个主语从句,主句谓语动词用单数 When and where we will go is not certain 3 如果用and连接两个或两个以上的主语从句作主语时，主句谓语动词用复数 When they will start and where they will go have not been decided yet. What he said and what he did were different. 4 what和who引导的主语从句，主句谓语动词的数应与主句中的表语保持一致 What he said was true. (表语是形容词时,谓语动词用单数) What they did (was in vain. (表语是介词短语时,谓语动词用单数) What I want are these books. (表语是复数名词时,谓语动词用复数) What I want is money. (表语是单数或不可数名词时,谓语动词用单数) 学科网（北京）股份有限公司 $$