必修三Unit4主语从句
主语从句(人教版高中英语必修三unit4)
主语从句后置!
为了避免主语冗长,句子头重脚轻,经常用it作 形式主语,主语从句放在后面作真正的主be late is certain. -- It’s certain that we shall be late.
1. That the earth is round is known to all.
Correct or not?
10
*That she wants to know is when the party
will be held .
×
What she wants to know is…….
Pay attention:此主语从句缺少成分-宾语， 故用作成分的what来引导，而不用that。
It is a fact that……
事实是……
It + 不及物动词 ＋ that从句
It appears that…
似乎…
It happens that ….
碰巧…
It occurred to me that…… 我突然想起……
*__It_i_s_a__p_it_y_t_h_a_t__(很遗憾)we lost the match.
What seems easy to some people seems difficult to others. Which side will win is not clear.
3)连接副词when，where， how， why等
Why he did it remains a mystery. When they will start is not known yet. How he became a great scientist is known to us all.
必修3：Unit4主语从句
summary
一、主语从句在句子中扮演主语的角色；
二、要不出现在句首，要不放在句末。
三、3种用法：
1. 由 -wh 引导 （what; who; when; where; why; how; whether…)
2. 由 that 引导
3. 由 It 做形式主语
1）It is + 名词 + 从句 2）It is + 形容词 + 从句 3）It + 动词（vi/vt) + 从句 (区分系动词) 4）It + 被动 + 从句
4）It + 被动 + 从句
It is reported that… 据报道……，
It is said that… 据说………
对比 what 和 that 的用法
用 what 和 that 填空。
1）_____ Trump did in public astonished the others. 2）_____ Trump did something in public astonished
状语从句 他养了条狗子，因为他寂寞。
主语从句是干啥的？
作主语的
主语从句的位置有 2 种情况： 1）主语从句 + 谓
谓 主
What you say is always right.
你说的都对。
主语从句的位置有 2 种情况： 2）it 作形式主语：It + 谓 + 主语从句
形式主语 谓
It is important that we eat well.
形式主语
主语从句
2）It is obvious that we can not finish the task on time.
必修三Unit4主语从句
必修三Unit4主语从句（Noun Clauses as the Subject）主语：是句子所要说明的人或事物，是句子的主体，主语的位置通常在句首，一般不省略，是谓语的陈述对象；表示句子说的是"什么人"、“什么事”、“什么东西”、“什么地方”等等。
通常名词、代词、数词、动名词、To do不定式、一个句子都可以做主语。
谓语：是对主语动作或状态的陈述或说明, 指出“做什么”、“是什么”或“怎么样”. 谓语动词的位置一般在主语之后。
找出句子的主语A tree has fallen across the road.You are a student.To find your way can be a problem.Smoking is bad for you.“How do you do?” is a greeting.What she said is not yet known.That we shall be late is certain.It is certain that we shall be late.在句中起主语作用的从句叫，它是名词性从句之一。
How the book will sell depends on its author.That he is the best student in the class is obvious主语从句用法归纳：(一)语序主语从句使用，其通常结构为“引导词+ 主语+ 谓语+ 其他成分”；但当连接代词同时充当从句主语时，其结构为“连接代词+ 谓语+ 其他成分”，。
That he will come and help us is certain.How the book will sell depends on its author.(二)引导词①that引导主语从句时，也任何成分，但通常省略.That they are badly in need of help is quite clear.但是这类句子在大多数情况下会放到整个句子的后部去，而用代词it作形式主语。
【高一同步教程】高中英语必修3 Unit4语法：主语从句讲解及练习
高中英语必修3 Unit 4语法教学案Section_ⅢGrammar—主语从句语法图解【探究发现】①What it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe.②The earth became so violent that it was not clear whether the shape would last or not.③What is even more important is that as the earth cooled down, water began to appear on its surface.④It was not immediately obvious that water was to be fundamental to the development of life.⑤What many scientists believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans and seas.⑥So whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved.【我的发现】(1) 以上黑体部分在句中作主语。
(2) ①句中的what在从句中作表语，但⑤句中的what在从句中作宾语；③句中的what在从句中作主语。
(3) ②⑥句中的whether意为：是否。
必修3 unit4 主语从句
It occurred to me that I hadn’t finished my homework. It happened that I saw him yesterday. It makes no difference whether he will attend the meeting or not.
4.Will tell me how I( can keep fit 宾语从句 ) and healthy? 5.His trouble is where he can find (表语从句 ) a new job. 6.What is needed (主语从句 ) for the space trip is careful preparation.
It is believed that the couple have left the country. It is reported that the project will be completed. It was said that he had gone abroad to study medicine.
用it作形式主语的主语从句
It + be + 过去分词 ＋ that从句
寻找主语从句
连接词
It is believed that… 人们相信… It is said that…… 据说… It is known to us/all that …. 众所周知…
翻译下列句子：
重点难点
It作形式主语
1.The problem was who could do the (表语从句 ) work. (主语从句 2.Who will go ) makes no difference. 3.Do you know whom John Adams was (宾语从句 ) speaking to.
人教必修三 Unit4 主语从句详细讲解课件56PPT
that 只有引导定从才做成分
• 5．what与that在引导主语从句时的区别 • what引导主语从句时在从句中充当成分，如
主语、宾语、表语等；that则不作任何成分， 只起连接作用。
• ①What has made him mad is not known yet. • (what在从句中作主语) • ②What you said yesterday is right. • (what在从句中作said的宾语) • ③That she is still alive is a consolation. • (that不作任何成分)
(引导名词性从句的关联词):
从属连词 that, whether, if，
(不作成分）
连接代词 what, who, whom, （作成分） whose, which, wh+ever 连接副词 when, where,why,how
（作状语）
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1.引导词 that
that放在句首引导主语从句，在主语从句中 不充当任何成分也无实际意义。但是不能省略。
It + be + 名词 ＋ that从句
It is a pity that… It is a surprise that …. It is a fact that……
遗憾的是…… 令人惊奇的是…… 事实是……
It + 不及物动词 ＋ that从句
It appears/seems that… 似乎……
★_W__h_a_t he offers is what I need.
★ _W__h_at__ they are most interested in is
how they can produce more and better cars.
高中英语必修三Unit4-主语从句
It happened that...
碰巧……
It occurred to me that…我突然想起…
It appears/seems that… 似乎，好像…
It turned out that… 原来…
*_I_t_h_a_p_p_e_n_e_d__t_h_a_t_(刚好)I was out yesterday.
主语从句的规律：
例4. That whether he will help others is a fact.
正：That he will help others is a fact.
规律四、主语从句中的连词不能重叠使用。
主语从句的规律： 例5. When he will come are a puzzle. 正：When he will come is a puzzle.
4) 连接副词when, where, how ,why
1.When we will leave（我们什么时候离开） hasn’t been decided. 2.How he got there (他怎么到那的） is a secret. 3. Why he cried (他为什么哭）is not clear. 4. Where the meeting （会议将在哪里举行） will be held is not known.
主语是？
Which part serves as subject in each sentence? 1. You are a student. 2. Smoking is bad for you. 3. To find your way can be a problem. 4. “How do you do?” is a greeting.
高中英语 人教版必修三第四单元语法：主语从句
Unit4 Astronomy:the science of the stars主语从句（The Subject Clause）（一）主语从句概念：在复合句中充当主语的句子，叫做主语从句。
句子结构：“主语从句（引导词+主语+谓语..）+谓语动词+句子其它...”What he said is of great importance .他所说的很重要。
That prices will go up is certain .物价要上涨是肯定的。
（二）主语从句引导词：连词that（无词义），,whether（是否）连接代词who/ who（谁）, whose（谁的）,what（...的事）,which (哪一个）连接副词when（什么时候）,where（哪里）,how（如何/怎么）,why （为什么）（1）that引导主语从句，本身无词义，在从句中不做成分，但不可省略。
eg That Tom passed the exam made hisparents happy .汤姆通过（2）whether引导主语从句，意为“是否”，在从句中不做成分，不可省略，位于句首时不能用if 。
Whether we ‘ll go camping tomorrow dependson the weather.明天我们是否去野营取决于天气。
（3）what引导主语从句，意为“...的事，”在从句中做主语、宾语、表语，不可省略。
What is needed for the space trip is careful preparation .（what 在从句作主语）去太空旅行所需要的就是仔细的准备。
What they want is a good book.（what 在从句作宾语）他们想要的就是一本好书。
（4）其它特殊疑问词引导的主语从句：注意特殊疑问词引导的主语从句要用陈述语序。
Who will do it doesn’t matter.谁要做这件事没关系。
人教高中英语必修3Unit4主语从句(共17张PPT)
Subject Clause.
主语从句三要素
How he became a great scientist is
known to us all.
Is what you told me really true?
不谓从 能语句 省动用 略词陈 关常述 联用语 词单序
一, 主语从句的连接词
1. that 只起连接作用，本身无意义，不充当任何 成分，但不能省略。
That she left him made him heart-broken. That he is still alive is a good news to us.
That he was chosen made us very happy.
=>It made us very happy that he was chosen.
用it 作形式主语的结构(1)
(1) It is ＋ 名词 ＋ 从句
It is a fact that …
事实是…
It is an honor that
…非常荣幸
It is common knowledge that
1. What you left are only several old books. 2. What you said is of great importance. 3. What he says and does doesn’t concern me. 4. What he says and does don’t agree.
tomorrow is not important. _W__h_ic_h__ class will win the football game is not clear. _W__h_o_ will meet him is not decided.
人教版高中英语必修三单元四Unit4主语从句(共16张PPT)
他何时何地出生的还不清楚。
When they will start and where they will go have not been decided yet.
他们将在什么时间动身以及要去哪里还没有定 下来。
1. It is likely that he is the winner of this game.
•
3.It＋be＋过去分词＋that从句
(said, reported, thought, expected, believed等) It is said that Mr.Green has arrived in Beijing.
据说格林先生已抵达北京。
4.It＋不及物动词＋that从句
(seem, happen等) It happened that I was out that day.
•
4、All that you do, do with your might; things done by halves are never done right. ----R.H. Stoddard, American poet做一切事都应尽力而为，半途而废永远不行6.17.20216.17.202110:5110:5110:51:1910:51:19
主语从句
一、定义 主语从句是在复合句中作句子的主语。
What I want is a new bicycle. 我想要的是一辆新自行车。
二、主语从句的引导词
1. 连词that, whether (1)that在从句中不作成分,无词义,不能省略 That she could come to help us made us very happy.
人教版高中英语必修三课件：Unit4主语从句(共23张PPT)
13、He who seize the right moment, is the right man.谁把握机遇，谁就心想事成。21.8.2521.8.2504:38:2904:38:29August 25, 2021
•
14、谁要是自己还没有发展培养和教育好，他就不能发展培养和教育别人。2021年8月25日星期三上午4时38分29秒04:38:2921.8.25
{ 导 主语 His job is important. What he does is important. 主语从句的定义：
在句中充当主语的从句叫做主语从句。
Subject Clauses 主语从句
思Task1: Find the sentences which are subject clause in the reading passage, then underline the subject clauses.
• ①It+be+__形__容__词____+that从句
(obvious, true, natural, surprising, wonderful, possible, likely, certain, probable)
• Eg:显然他撒谎了。
___It__w_a_s__o_b__v_i_o_u_s__t_h_a_t_h__e_t_o_l_d__a_l_i_e_.______
down, water began to appear on its surface. • 4. It was not immediately obvious that water was to be
fundamental to the development of life. • 5.What many scientist believe is that the continued
必修三unit4语法讲解主语从句 Grammar
Section Ⅲ Grammar —主语从句在主从复合句中，充当主语的从句，即为主语从句。
一、主语从句的连接词1．连接词that和whether(1)that在从句中不充当任何句子成分，只起连接作用，但不可省略。
①That Whitney Houston died upset her fans all over the world.惠特尼·休斯顿的离世令全世界的粉丝感到难过。
(2) whether在从句中不充当任何句子成分，起连接作用，意为“是否”，不可省略。
②Whether the plan will be carried out is still unknown.这个计划是否会实施还不知道。
即学即练11－1.完成句子①她能来帮助我们使我们很高兴。
_________________________ made us very happy.②他被选为(be chosen as)志愿者(volunteer)让我们感到高兴。
____________________________ made us happy.③我们明天是否举行派对取决于天气。
____________________________ depends on the weather.④(湖南高考)Everyone in the village is very friendly. It doesn't matter ________ you have lived there for a short or a long time.A．why B．HowC．whether D．when2．连接代词(who，whose，whom，what，which，whichever，whoever, whomever, whatever连接代词引导主语从句，在从句中可以作主语、宾语、表语或定语。
①Who will take his place is not important.谁将代替他并不重要。
人教版高中英语必修三课件：Unit4 主语从句
(3) 主谓一致
is When he will come _______(be) a puzzle. When they will start and where they will go are ______(be) decided so far. is When and where they will go _____(be) decided so far. is that book. What he needs____
检
I. 用适当的连接词填空，使句子意思完整。
Why 1. __________ he didn't attend the meeting yesterday wasn't quite clear. 2. __________ Which team will win the match is still unknown. Whoever comes to the party will receive a present. 3. ___________ that 4. It's reported ___________ three people were killed in the accident How 5. _____________ he solved the problem successfully interested all of us. 6. ____________ Who/what is to be sent there to solve the problem hasn't been decided.
不及物动词及短语 ④It+__________+( 连接词不固定)从句
（seem/happen/appear/matter/turn out/occur to/makes no difference等） Eg:你今天来或者明天来都没关系。 ___________________________________ It doesn't matter whether you come today or tomorrow. ____________
人教版高中英语高三必修3 Unit4 理解【主语从句】的用法
ANALYSIS
谢谢聆听
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回到第9 页
13
达标测评
考考你
ANALYSIS TEST
4.单项选择
____ is a fact that English is accepted as an
international language.
A. There
B. This
C. That
D. It
回到第9 页
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达标测评
考考你
ANALYSIS TEST
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ANALYSIS
总结归纳
请用表格演示主语从句的句型结构。
主语从句的句型结构
形式主语
真正 主语
be+表语（表语：名词， 形容词）
It
不及物动词
主语 从句
be+过去分词/动词的被动语态
记忆技巧：“it”形“从”真，成句型，主语从句构成形。
8
ANALYSIS
实际操练
根据图片和给出的单词，用it作形式主语，主语从句 当真正主语的语法进行造句。
5.把下面的文章补充完整。
In my opinion, it is very important _I_s_ho_u_ld_l_ea_r_n _ _g_ra_m_m_a_r_w_e_ll __ (我学好语法) because it can help me with my writing and my sentence structure. __I_t __ is known to all that grammar is really a bridge to success. Believe it or not, it doesn’t matter __w_h_et_he_r_ we can recite all those grammar rules. What we need to do is try to understand and use the language.
必修3-unit4主语从句1
必修3-u n i t4主语从句1主语从句【教学内容】主语从句【教学目标】熟练掌握不同连接词引导的主语从句【教学重难点】连接词的使用、It作形式主语的常见句型【教学过程】●什么是主语从句：在主句中起主语作用的从句称为主语从句。
Eg:I need a good meal.(I是主语）What I need is a good meal.（What I need 整句话作主语）●其连接代词主要有三类：①从属连词：that,whether,if②连接代词：who(ever),whom(ever),whose(ever),what(ever),which(ever)③连接副词：when(ever),where(ever),how(ever),why▼that 引导的主语从句①that置于句首的主语从句从属连词that在主语从句中不作任何成分，也没有实际意义，只起连接作用。
→That he will come to the conference has excited every one of us.他要来参加会议这使我们每一个人都十分激动。
→That in some countries women are still treated unequally is unfair.在一些国家妇女仍然受到不平等对待是不公平的。
②形式主语it替代主语从句常见的it替代主语从句的句式主要有如下几种：► It+be+形容词（certain,clear,necessary,likely,obvious,probable,etc.)+that从句：→It is certain that most of the farmers have brought in more money by all means.很明确大多数农民通过各种方式赚了很多钱。
→It is likely that there will be a snowstorm tomorrow.很可能明天会有一场暴风雨。
必修三 unit4 主语从句
主语是动作的发出者或受到描述的对象。
通常位于谓语动词或系动词之前。
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一、主语从句的定义： 在复合句中位于谓语动词或系动词之前充当主语 的句子，叫主语从句。 That he is still alive is a wonder.
二、主语从句的构成： 引导词 + 简单句 + 谓语动词/系动词 + 其他成分.
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1. that
2. that引导主语从句, that在从句中只起连接作用
，
3.
不作成分，没有意义，不能省略。
That he will come is certain.
2. whether
1.1) whether引导主语从句，译为“是否”, 不能省略
。
2. if 不能引导表语从句。
Whom she borrowed money from still puzzled him.
Which side will win is not clear.
What she said today was quite right.
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When he will be back depends on the weather. Where the test will be given is not yet decided. Where and when he was born is a secret.
It + 谓语动词/系动词 + 宾语/表语 + 主语从句. 例如:
That we shall be late is certain. = It is certain that we shall be late. 1. That the earth is round is known to all. = It is known to all that the earth is round. 2. whether they would support us was a problem . = It was a problem wh精e选t版h课e件rpptt hey would support10us.
人教版高中英语必修三unit4语法(9张PPT)
*__It_i_s_r_e_p_o_r_t_e_d_t_h_a_t___(据报
道)20peoplewerekilledintheaccident.
*_I_ti_s_s_u_g__g_e_s_t_e_d_t_h_a_t_____(建
议)weshouldeatmorevegetableanddomoreex
e注rc意is3e：. 主语为从句时，谓语动词一般要用单数形 式；但如果what引导的从句做主语，并且代表复 数概念（常可从表语上看出），则谓语动词常用 复数形式
Whatweneed___i_s____water.我们所需要的是水。 Whatweneed________usefulbooks.我们所需要 的是一些有用的书a。re
高中英语课件
madeofcanruohanxing
SubjectClauses 主语从句
1.主语从句概念 主语从句就是从句在主句中作主语的名词性从句。
2.ConjunctionsofNounClauses(引导主语从句的
关联词):
从属连词 that,whether,（注意if不 (不作成分） 能引导）
连接代词 wቤተ መጻሕፍቲ ባይዱat,who,which,whom, （作成分） whose,wh+ever
连接副词 （作状语） when,where,how,why
3.主语从句注意事项
注意1：that在从句中只起连接作用，不充当句子 成分，且本身无实际意义。
whether在从句中起连接作用，不充当句子成分， 不能用if代替.
It’sapity/ashame//afact/goodnews/nowonder/ acommonknowledge…that…(遗憾的是/事实是/ 好消息//难怪/众所周知）
必修3-unit4主语从句1
主语从句【教学内容】主语从句【教学目标】熟练掌握不同连接词引导的主语从句【教学重难点】连接词的使用、It作形式主语的常见句型【教学过程】●什么是主语从句：在主句中起主语作用的从句称为主语从句.Eg：I need a good meal.（I是主语)What I need is a good meal.（What I need 整句话作主语）●其连接代词主要有三类:①从属连词：that，whether,if②连接代词：who（ever）,whom(ever），whose（ever),what(ever)，which（ever)③连接副词：when(ever），where（ever）,how（ever),why▼that 引导的主语从句①that置于句首的主语从句从属连词that在主语从句中不作任何成分，也没有实际意义，只起连接作用。
→That he will come to the conference has excited every one of us.他要来参加会议这使我们每一个人都十分激动。
→That in some countries women are still treated unequally is unfair。
在一些国家妇女仍然受到不平等对待是不公平的。
②形式主语it替代主语从句常见的it替代主语从句的句式主要有如下几种：► It+be+形容词（certain,clear，necessary，likely,obvious,probable，etc.）+that从句：→It is certain that most of the farmers have brought in more money by all means.很明确大多数农民通过各种方式赚了很多钱.→It is likely that there will be a snowstorm tomorrow。
很可能明天会有一场暴风雨。
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必修三Unit4主语从句(Subject Clause)
➢定义:
在句子中担当主语的是一个从句，这个从句就叫做主语从句。
➢位置：
1.通常放在主句谓语动词之前
That he will succeed is certain. Who will be our monitor hasn't been decided yet.
Whether he will join us won't make difference. How the book will sell depends on its author. What caused the accident remains unknown.
2.由形式主语it代替，而本身放在句子末尾。
It doesn’t matter whether he is wrong or not.
➢辨别下列从句的类别(1-6)：主从；宾从；表从；主从；宾从；主从
➢主语从句的连接词
引导主语从句的连接词可分为三类：连接词：that, whether / if；连接代词：what, which who, whom, whose, whatever, whoever, whichever等；连接副词：when, where, how, why, whenever, wherever等。
●that:1.无词义；2.在主语从句中不作成分；3.一般不能省略（尤其在句首时）
That he will come and help us is certain. That he is the best student in the class is obvious.
●Whether / if: 1.有词义：“是否”；2.在主语从句中不作成分；3. whether引导的主语从句可
放句首、句末；4. If引导的主语从句不能位于句首。
Whether we will succeed is still a question. If we will succeed is still a question. (×)
It is not known whether / if he will come.
what, whatever, who, whoever, whose, which, whichever
when, where，why, how等。
1.有词义；
2.在主语从句中作成分。
What he is has nothing to do with you. Whose ticket this is has not been found out.
When the test will be given is not yet decided. Whatever you did is right.
➢如何选择连接代词和连接副词
在主语从句中，连接词的选择要看这个从句的句子结构，假如根据意思判断为缺少主语，宾语，表语等时应该考虑who, whoever, which, whichever, what, whatever, whom, whomever；如果缺少定语则想到whose, which；如果缺少状语则应该选择how, where, when, why等。
因此要想做好题目首先得了解句子成分。
What I can’t understand is why he has changed his mind.
（缺少understand的宾语，意为“…的事”）
Whoever breaks the law will be punished.（缺少breaks的主语，意为“无论谁”）
➢主语从句后置！
为了避免主语冗长，句子头重脚轻，主语从句作主语时通常用it作形式主语，主语从句放在后面作真正的主语。
That he finished writing the composition in such a short time surprised us.
=It surprised us that he finished writing the composition in such a short time.
Whether he will come or not doe sn’t matter. =It doesn’t matter whether he will come or not. Who will do that job is not yet decided. =It is not yet decided who will do that job.
➢用it作形式主语的that从句有以下搭配关系：
1. It + be +形容词+ that从句
It is necessary / important / obvious / certain / natural…that…
It is necessary that the problem should be discussed at once.
2. It + be +名词+ that从句
It is a pity / a shame / no wonder/ an honour / no surprise…that…
It's a wonder that he didn't fail.
3. It + be + -ed分词+ that从句
It is believed / reported / said/ thought/expected /known that…
It is said that he‘s got married.
4. It +不及物动词+ that分句
It appears/seems /happens/matters/ occurred to that…
It seems that he has seen the film.
➢主语从句的语序和时态
【观察】
Why he did it will remain a puzzle forever. How this happened is not clear to anyone. What you need is more practice. What you need was mentioned by him.
归纳：主语从句的语序用陈述语序；主语从句的时态不受主句的时态影响和限制。
➢主语从句作主语时主句中的谓语动词的单复数情况
How he worked it out is still a secret. Who will write the poem has not been decided yet. How it was done was a mystery. Where she has gone remains not known yet.
What we need is more time. What we need are many more books.
总结：当主语从句作主语时，主句中的谓语动词一般用第三人称单数，但what引导主语从句的主句谓语动词的形式须根据句子的意思来判断或根据主句中的表语来决定。
What they makes in this factory TV sets.
What he’d like most for a birthday present a camera.
It was my suggestion that made him confident of success.
→My suggestion made him confident of success.（句子仍然成立，是强调句）
It was my suggestion that he needs more practice.
→My suggestion he needs more practice.（句子不成立，是主语从句）
➢改错答案：1. shall we →we shall; 2. That you; 3. That →It 4. are →is; 5. If →whether
➢用连接词填空答案：1. that; 2. Whoever; 3. That; 4. Whether; 5. Which
➢用主语从句翻译句子答案
1. Where he lives is a puzzle.
2. It is certain that nothing will prevent us from coming here.
3. That she has just given birth to a healthy baby girl made us excited.
➢选择题答案：1-5: CBACB 6-10: DCDAD。