Unit 5 Discover Useful Structures 主语从句用法（ppt课件）-2022新人教版（2019）《高中英语》选择性必修第一册.pptx

1、5.To find your way can be a problem.4.Smoking is bad for you.1.Jake works hard.2.They are students.3.The old should be respected.Whats the subject?（什么是主语和主语从句？）（什么是主语和主语从句？）6.What she said is not yet known.结论：结论：主语是句子说明的人或事物，一般放在主语是句子说明的人或事物，一般放在_。主语从句是名词性从句的一种,在复合句中作主语,相当于名词。主语从句的位置可以在句首,也可以用it作形式主

2、语,主语从句放在后面。连接词有从属连词，连接代词和连接副词句首句首主语主语That she survived the accident is a miracle.她在事故中幸免于难简直是个奇迹。她在事故中幸免于难简直是个奇迹。Whether the plan will be carried out is still unknown.=It is still unknown if/whether the plan will be carried out.这个计划是否会实施还不知道。这个计划是否会实施还不知道。that _成分，成分，_意义，意义，_省略。省略。whether _成分，成分，_意义

3、，译为意义，译为_。从属连词从属连词引导主语从句只起引导作用，在主语从句中引导主语从句只起引导作用，在主语从句中不充当任不充当任何成分何成分。可用可用it作形式主语，作形式主语，if引导的从句后置作真正主语。引导的从句后置作真正主语。不做不做是否是否无无不能不能不做不做有有1.从属连词：that、whether、ifWho will go is unknown.who在主语从句中充当在主语从句中充当 _,译为译为 _。What we need is more time.what在主语从句中充当在主语从句中充当 _,译为译为 _。Which book I shall choose hasnt b

4、een decided.which在主语从句中充当在主语从句中充当 _,译为译为 _。Whoever breaks the law will be punished.whoever在主语从句中充当在主语从句中充当 _,译为译为 _。2.连接代词:who、whoever、whom、whose、what、whatever、which、whichever宾语宾语什么什么主语主语谁谁主语主语无论谁无论谁定语定语哪一个哪一个When we will leave hasnt been decided.when在从句中充当在从句中充当 _,译为译为 _。Where the meeting will be h

5、eld is not known.where在从句中充当在从句中充当 _,译为译为 _。Why he cries is not clear.why在从句中充当在从句中充当 _,译为译为 _。How she keeps healthy is a secret.how在从句中充当在从句中充当 _,译为译为 _。3.连接副词：when、where、how、why状语状语什么时候什么时候状语状语哪里哪里状语状语为什么为什么状语状语怎样怎样1.Whether the patient will be taken _ unknown.单个从句做主语，大多数使用单个从句做主语，大多数使用_ (单数？复数？单数

6、？复数？)2.When and where the patient will be taken _ unknown.由两个连接词引导同一个主从，谓动使用由两个连接词引导同一个主从，谓动使用_(单数？复数？单数？复数？)3.When the task can be finished and whether he can have a rest _ unknown.主语为主语为and连接的两个主从时，谓动使用连接的两个主从时，谓动使用_(单数？复数？单数？复数？)4.What he wants most _ staying with his family.What they need _ mask

7、s(口罩口罩).what在主从中做宾语时，谓语的单复数取决它后面的表语。在主从中做宾语时，谓语的单复数取决它后面的表语。主语从句一律用主语从句一律用_语序，即主语在前，谓语在后。语序，即主语在前，谓语在后。单数单数is单数单数is复数复数areis are陈述1.1.主谓一致主谓一致2.2.主语从主语从句的句的语序语序注意注意1 2 31 2 3从属连词从属连词(不作成分）不作成分）连接代词连接代词（作主作主,宾宾,表表,定语定语）连接副词连接副词（作状语）（作状语）what,who,whom,which,whose,wh+everhow,when,where,whythat(无意义无意义),

8、whether（句首、中）（句首、中）/if（中）：是否（中）：是否Summary“缺什么补什么缺什么补什么”原则原则缺主语，指人用缺主语，指人用_，指物用，指物用_缺宾语，指人用缺宾语，指人用_，指物用，指物用_缺时间状语用缺时间状语用_；地点状语用地点状语用_；原因状语用原因状语用_；方式状语用方式状语用_；定语用定语用_；什么都不缺用什么都不缺用_，缺，缺“是否是否”_”_whowhowhatwhatwho/whomwho/whomwhatwhatwhenwhenwherewherewhywhyhowhowwhich/whosewhich/whosethatthatwhetherwhet

9、her“缺什么补什么”是指。That all countries work together is important.It is important that all countries work together.主语从句为了避免头重脚轻现象主语从句为了避免头重脚轻现象,用用itit做做_，而把从句放在后面充当而把从句放在后面充当_。真正的主语形式主语3.3.主语从句主语从句太长怎么办？太长怎么办？1.It+be+形容词+主语从句 做.是.的形容词clear,obvious,likely,probable,true例：1.It is not clear whether he told a

10、lie.2.It+be+过去分词+主语从句 据.said,reported,believed,thought,announced过去分词例：1.It is said that they are identical twins.此句型中的形容词是important,necessary等时，从句应使用虚拟语气例：It is important that we(should)learn English well.若过去分词是suggested,ordered,required,advised,requested等表示建议、要求、命令等词时，从句应该使用虚拟语气。例：It is suggested t

11、hat students(should)make their bed by themselves.3.It+be+名词+主语从句 做.是.的名词a pity，an honor，a good idea，a fact,a/no surprise，no wonder.例：It is a pity that he missed such an interesting film,4.It+不及物动词+主语从句seem,happen,appear,look,occur,turn out 不及物动词例：It happened that they were out that day.碰巧那天他们不在家。It

12、seems that it is going to rain.看起来要下雨了。5.It+及物动词+宾语+主语从句及物动词worry,shock 例：It shocks me that he failed in this exam.他没通过考试，震惊到我了。【即时演练】1._is a fact that English is being accepted as an international language.2.It is uncertain _ he can come to Jennys birthday party or not.3._ he made an important speech at the meeting was true.4._ is known to us all that America is a developed country.5.Every year,_ makes the most beautiful kite will win a prize in the Kite Festival.6.Your support is important to our work._ you can do helps.ItwhetherThatWhateverItwhoeverThank you for your watching