1、主语从句 主语从句的定义主语从句是一个从句，它在句子中充当主语的角色。也就是说，整个从句表示的是谁或者什么进行了句子的动作或者状态。主语从句通常由一个连接词引导，并且可以独立成为一个完整的句子。主语从句的分类 1.由 that 引导的主语从句这种从句中，that 作为连接词，引导从句，但它在从句中不充当任何语法成分，也没有实际意义。-That he was late was obvious to everyone.（他迟到是众所周知的。）2.由 whether/if 引导的主语从句whether 或 if 引导的主语从句通常用于表达疑问或不确定性。注意，If通常不用于正式文体中。-Whethe
2、r he will come is uncertain.-If he will come is uncertain.(非正式)-Whether he will come or not is still unknown.（他是否会来还不清楚。）3.由连接代词或连接副词引导的主语从句连接代词WhatWhoWhichWhoseWhateverWhicheverwhoever连接副词WhenWhereWhyHow连接代词（who,what,which,whom 等）和连接副词（why,how,when,where 等）引导的主语从句，它们在从句中充当一定的语法成分。-Who will win the
3、election is still unknown.-How he managed to do it remains a mystery.-What she wants to do is a secret.（她想要做什么是个秘密。）-Why he left is a mystery.（他为什么离开仍然是个谜。）4.必须用 it 作形式主语的主语从句当主语从句较长或者结构较为复杂时，为了避免句子显得头重脚轻，通常使用 it 作为形式主语，而将从句放在句子的后半部分。-It is clear that he has made a mistake.-It is uncertain whether t
4、hey will arrive on time.-It is important that you should study hard.（你努力学习是很重要的。）-It is unknown whether he will accept the job offer.（他是否会接受这份工作邀请还不清楚。）练习1.将以下句子改为使用that引导的主语从句：-She is still alive.This is a miracle.答案-That she is still alive is a miracle.2.将以下句子改为使用whether或if引导的主语从句：-He will come.Th
5、is is uncertain.答案-Whether he will come is uncertain.3.将以下句子改为使用连接代词或连接副词引导的主语从句：-The person will win the election.This is still unknown.答案-Who will win the election is still unknown.4.将以下句子改为使用it作为形式主语的主语从句：-He has made a mistake.This is clear.答案-It is clear that he has made a mistake.5.请将下列句子改写为包含
6、主语从句的句子：-He knows that she likes him.-They are not sure if he can finish the work on time.-The question is what to do next.答案-What he knows is that she likes him.-It is not sure whether he can finish the work on time.-What the question is is what to do next.6.请选择正确的连接词完成下列句子：-_ he will come is uncer
7、tain.(whether/what)-_ she does is a surprise.(that/why)-_ he left is a mystery.(where/if)答案-Whether he will come is uncertain.-What she does is a surprise.-Where he left is a mystery.练习1._ she loves dancing is no secret to her friends.2._ he will join the army depends on his graduation results.3._ t
8、hey had a great time at the party is obvious from their笑容.4._ we should respect each other is a principle of good manners.5._ she is the best student in the class is widely recognized.练习6._ they plan to delay the meeting until further notice has been announced.7._ he has a passion for photography is
9、 evident in his work.8._ you have finished your homework is not yet clear.9._ the sun rises in the east is a fact.10._ she can speak multiple languages surprises many people.练习11._ they are planning to move to a new city is a possibility.12._ he passed the exam with flying colors pleased his parents
10、.13._ you are late for school again is unacceptable.14._ the economy will recover next year is still uncertain.15._ she will accept the job offer is uncertain at the moment.练习16._ he has changed a lot over the years is undeniable.17._ they will be able to find a solution to the problem remains to be
11、 seen.18._ you eat healthily is important for your well-being.19._ he was promoted to manager is a well-deserved achievement.20._ she will attend the conference is still up in the air.练习21._ they had to cancel the trip due to bad weather is regrettable.22._ he managed to solve the problem on his own
12、 is impressive.23._ you study hard will determine your success in the future.24._ she has a strong interest in music is clear from her performances.25._ they are coming to the party tonight is a relief.练习26._ the government will approve the new project is uncertain.27._ he will be able to return to
13、work next week is hopeful.28._ she wants to pursue a career in art is her dream.29._ you understand the instructions is crucial for the task.30._ the team will win the championship is a matter of speculation.答案1.That she loves dancing2.Whether he will join the army3.That they had a great time at the
14、 party4.That we should respect each other5.That she is the best student in the class答案6.That they plan to delay the meeting7.That he has a passion for photography8.Whether you have finished your homework9.That the sun rises in the east10.That she can speak multiple languages答案11.That they are planni
15、ng to move12.That he passed the exam13.That you are late for school14.Whether the economy will recover15.Whether she will accept the job offer答案16.That he has changed a lot17.Whether they will find a solution18.That you eat healthily19.That he was promoted20.Whether she will attend the conference答案2
16、1.That they had to cancel the trip22.That he managed to solve the problem23.That you study hard24.That she has a strong interest in music25.That they are coming to the party答案26.Whether the government will approve the project27.Whether he will be able to return to work28.That she wants to pursue a career in art29.That you understand the instructions30.Whether the team will win the championship
