高中英语Module2 rSectionⅢGrammar_表语从句和主语从句教案含解析外研版选修7
Unit3 period3 grammar主语从句和表语从句
表语从句
定义： 定义：一个从句在复合句中作主句的表 语，这个从句就叫作表语从句。 这个从句就叫作表语从句。 1.The problem is that millions of people die of illnesses caused by smoking. 2.The question remains whether we can win the people. 3.That’s just what I want.
1 Maria has to be baby-sit. That’s ______ she can’t come out with us. A. why B. how C. when D. what 2 ---I went to see you at about ten this morning, but you were not in the office. --- Oh, that was probably________ I was talking with the headmaster. A. when B. why C. what D. that
1. Choosing the right dictionary depends on ______ you want to use it for. (2007 江苏卷 江苏卷) A. what C. how B. why D. whether
2. Could I speak to_________ is in charge of International Sales ,please? (2007 山东卷 山东卷) A. anyone C. whoever B. someone D. no matter who
2. 连接代词 连接代词what，which，who, whom， ， ， ， whose等引导的表语从句。 等引导的表语从句。 等引导的表语从句 This is what I want to say. 这就是我想说的。 这就是我想说的。 3. 连接副词 连接副词when，where，how，why等 ， ， ， 等 引导的表语从句。 引导的表语从句。 This is how we overcome the difficulties. 这就是我们克服困难的方法。 这就是我们克服困难的方法。
人教版高一英语必修三 unit3 Grammar 名词性从句-宾语从句和表语从句课件
人教版高一英语必修 三 unit3 Grammar 名 词性从句-宾语从句和
My mother told me the sun ____ from the east. Tom asked me why KFC _____ its price again. (raise, rise)
rises raised
注意
用whether而不用if引导宾语从句情况
(whether/if 在宾从中不作成分, 表示“是否”,有时可互换) 1）介词+whether 3）whether to do
介词+宾语从句
l I lived in what you call “Ancient Greece”.
summary
介词 + whether + 陈述句 介词 + wh-词 + 陈述句
注意注意
l 宾语从句的时态必须与主句呼应： 1）主句—现在或将来时态，宾从—根据需要使用任何时态 2）主句—过去时态, 宾从—过去时态 【例外】: 主句—过去时态，宾从—一般现在时态 (宾从表示的是客观事实、自然现象或真理时)
My suggestion is that we (should) go and help him. 我的建议是我们去帮助他。
• 1.The trouble is ______ I have lost his addrtehsast . • 2.The reason ____ he was late was ____ he missed the first bus this morning. • 3.His proposal was that we _________ (collect)all the related information.
2019年高中英语Module2HighlightsofMySeniorYearSectionⅢGrammar_表语从句和主语从句教案含解析外研版选修
Section Ⅲ Grammar —表语从句和主语从句语法图解探究发现①My feeling is that they're going to be big one day.②But the big surprise of the evening was when I was elected prom queen!③China is no longer what it used to be.④The reason why I'm calling you is that I want to invite you to my birthday party.⑤That she has became an artist may have been due to her father's influence.⑥What we should do next remains unknown.⑦Whether it will do us harm remains to be seen.⑧It's a good thing that the exams are finished.[我的发现](1)以上句中，①～④句中黑体部分均引导表语从句，而⑤～⑧句中黑体部分则引导主语从句。
(2)由④句可知，主语为名词reason时，表语从句中的连接词要用that，而不用why。
(3)由⑤⑥句知，引导主语从句时，what要在从句中充当句子成分，而that不作任何成分，只在语法上起连接作用。
(4)⑧句中，it用作形式主语，代替that引导的主语从句。
一、表语从句1．定义在复合句中作表语的从句，叫作表语从句。
它位于主句的系动词之后，对主语进行解释、说明，使主语的内容具体化。
2．引导词[即时演练1] 用适当的连接词填空①My opinion is that we should communicate with parents frequently.②The problem is whether we can find them there.③This is what I should have done first of all.④This is where I don't agree with you.⑤The question is how we can get in touch with him.⑥The problem is who will come to replace her.⑦This is because it is raining outside.3．注意事项(1)that与what的区别that引导表语从句时，是连词，在从句中不作成分；what是连接代词，引导表语从句时，在从句中作主语、宾语、表语或定语。
unit3-grammar-宾语从句与表语从句
无义 1. The mother’s question was that she has no time to look after her daughter.
是否 2.The question is whether that boy will
turn up in time.
….的样子 3. Tom is no longer what he used to be .
4. I don’t know _w__h_e_t_h__eror not he is well.
5. I don’t know _w_h__e_th__erto go.
• 由疑问词引导的宾语从句 用who, whom, what,
when, where, how, whenever等关联词引导 时，连接词在从句中担当 一定成分，具有一定的意 义，从句语序要用陈述语 序。
if / whether
1. I asked her i_f_/_w__h_e_t_h_e_rshe had a bike.
2. We’re worried about _w__h_e_t_h_e_ rhe is safe.
3. I wonder __w__h_e_t_h_e_r_/_ifhe is well.
注意2：whether / if
A. 引导宾语从句时可互换. B. 位于介词后要用whether. C. 位于句首时要用whether. D. 引导表语从句, 主语从句, 同位语
1. He asked （谁能回答这个问题） _w__h_o_c_o_u_l_d__a_n_sw__e_r_t_h_e_q_u__es_t_io_n___.
2. Do you know__w_h_o_m__t_h_ey__a_re__w_a_it_in_g__for （他们在等谁）
unit3grammar宾语从句与表语从句
无义 1. The mother’s question was that she 2. has no time to look after her daughter.
是否 3. 2.The question is whether that boy will 4. turn up in time.
主 句 宾语从句
什么是宾语？
• I know him. • Do you have the time? • I think (that) she is beautiful. • Why don’t you pay attention to me?
宾语 位于谓语动词或者介词后
一、宾语从句的概念
•从句在复合句中作宾语的名词性从 句。 •位置：通常放在主句谓语动词（及 物动词）或介词之后。
• They asked me whether to go skating.
3.当与or not连用
I don’t know whether he’s free or not.
Mary asked whether I was doing my homework or not.
Practice time
3 和连接副词 where,how,why,when 引导的宾语从句
由从属连词 that 引导的宾语从句
注：that 在句中无词汇意义，在从 句中不能充当成分，在口语当中往往 e.g.省略
1.I hear (that) _h_e__w_i_ll_b_e__b_a_c_k_i_n_a_n__h_o_u_r_.
是否会下雨
译林版必修一Unit 2 Section Ⅲ Grammar——简单句、并列句和主从复合句
选词填空：and，but，or，so，for ①I’d like to go with you，_____a_n_d_____ I’m not busy. ②I can’t tell my cousin’s appearance，______fo_r_____ I have never seen her. ③Don’t run in the classroom，______o_r_____ you may hurt yourself. ④Surfing the Internet is fun，______b_u_t ____ it’s also a time waster. ⑤A snake bit him ______so______ he went to see a doctor at once. ⑥Come a little earlier next time，______o_r _____ you’ll miss the best part of the TV play.
Section Ⅲ Grammar——简单句、并列句和主从复合句
①We know that being a teenager is sometimes difficult. ②If your problem is a new one，write a post about it. ③You can look through these articles to find advice on your problem. ④It is likely that the matter has already been discussed on our forum. ⑤Our website has many articles about teenagers’ physical and mental health. ⑥Shall I send the book to you，or will you come to get it? ⑦The little girl who you saw yesterday is my cousin.
高中英语真题-高三Grammar宾语从句与表语从句
高中英语真题:高三Grammar宾语从句与表语从句名词性从句在复合句中起名词作用的从句叫做名词性从句。
名词性从句的作用相当于名词，因此主语从句、表语从句、宾语从句和同位语从句分别作主句的主语、表语、宾语和同位语。
主语从句：Who will win the match is still unknown.宾语从句：I want to know what he has told you.表语从句：The fact is that we have lost the game.同位语从句：The news that we won the game is exciting.引导名词性从句的连接词可分为三类：连接词(不充当从句的任何成分)：that ,whether ,if连接代词：what, who, whom, whose, which, wh+ever连接副词：when ,where ,how ,whyObject Clauses 宾语从句请对应写出句子成分I know him.（）（）（）I know who he is.（）（）（）请用横线画出下面句子的宾语从句部分。
1、I know him.2、Do you have the time?3、I think that she is beautiful.4、Why don’t you pay attention to me?总结：宾语通常位于谓_____________或者_____________后一、宾语从句的概念：宾语从句在复合句中作主句的宾语。
位置：通常放在主句谓语动词（及物动词）或介词之后。
句子结构：主句 +连词(引导词)+ 宾语从句e.g. She asked if these answers were right.We can learn what we do not know.He will talk to us about what he saw in theI don’t know where we will hold the meeting.通过观察，我们可以知道宾语从句的语序用陈述语序：连接词+主语+谓语+其他成分练习：1)Could you tell me______.A. you will get here whenB. when will you get hereC. get here when you willD. when you will get here2) Mother asked his son what ______for lunch at school.A. did he hadB. does he hadC. he hasD. he had3) Pointing to the young plant, he asked me ____ that was the one we had seen in the picture.A. whatB. ifC. whereD. how二、连接词1、从属连接词(不充当从句的任何成分)：that ,whether ,if 1）、 I hear (that) he will be back in an hour.2）、I want to know if /whether he will go to the park with us 注：1、由that 引导的陈述句性的宾语从句，在很多动词如say, think, wish , hope, see, believe, agree, expect, hear , feel 等动词后。
人教版高一英语必修三 unit3 Grammar 名词性从句-宾语从句和表语从句课件
二、predicative clause 表语从句
That is why we have given you the letter.
主语 系 动 词
表语从句
从句主语
连接词
从句谓语
从句宾语
表从的连接词
• 从属连词：that, whether, as if/though(好像), • 连接代词：who, whom, whose, what, which • 连接副词：when, where, why, how
whetherifwhetherwhether2与与ornot连用4用用if容易产生歧义时宾语从句中的否定转移?主句谓语动词是thinkconsidersupposebelieveexpectguessimagine等表示认为相信猜测等宾从谓语是否定含义将否定词放在主句谓语前但意义上否定的仍是宾从
人教版高一英语必修 三 unit3 Grammar 名 词性从句-宾语从句和
because, as(正如)
【缺啥补啥，啥都不缺用that】
宾语从句和表语从句
宾
You can what you want to do,
语
w
and
what you want to be.
have
be
表语从句
重重点点
表语从句的特殊句式
句式一：
The reason why…is that… ……的原因是…… Why… is that…
why
that
(should) collect
He asked _ for the vioDlin. A. did I pay how much B. I paid how much C. how much did I pay D. how much I paid
2018-2019学年18-19 Unit 3 Section Ⅲ Grammar——宾语从句和表语从句
Section ⅢGrammar——宾语从句和表语从句[语境自主领悟]一、名词性从句的连接词1．that引导的宾语从句由连接词that引导宾语从句时，that在句中不充当任何成分，在口语或非正式的文体中常被省去。
We learnt from his letter (that)he would come to Shanghai soon.从他的信中我们了解到他不久会来上海。
[名师点津]宾语从句中两种情况中的连接词that不能省略；①引导的第二个宾语从句前的that不可省；②在动词＋形式宾语it＋宾语补足语＋that引导的宾语从句中that不能省略。
He said(that)you were too young to understand the matter and that you were asked not to care about it.他说你太年轻，还无法理解这件事情，你也不要去管它。
We think it important that every citizen should obey the traffic rules.我们认为每个市民都应该遵守交通规则是很重要的。
[即时训练1]单句改错①He said he would give up the chance and he would try hard to look for another one.在and后加that②We found it strange no one would take the money.在strange后加that2．whether或if引导的宾语从句whether或if引导宾语从句时，在句中不充当成分，但是含“是否”之意，从句要用陈述语序。
I wonder whether/if we'll finish the task on time.我不知道我们能否按时完成这项任务。
I'll see whether/if I can advise him to accept it.我要看看我是否能劝他接受。
英语人教版必修学案：Unit Section Ⅲ Grammar——主语从句
Section ⅢGrammar——主语从句[思维导图][语法精讲]一、定义在主从复合句中充当主语的从句即为主语从句。
What surprised me is that everybody seemed to be very cold to her.让我吃惊的是每个人似乎对她都很冷淡。
It worried the woman that her son was always playing computer games.儿子一直在玩电脑游戏，这让这个女人很担心。
二、主语从句的连接词及其句法功能Who will do it doesn't matter.谁做这件事都没有关系。
What we need is more water.我们需要的是更多的水。
Whatever you do in your spare time should do no harm to others.无论你在业余时间做什么都不应该伤害其他人。
How this happened is not clear to anyone.这件事怎样发生的，谁也不清楚。
When we will have a meeting is an important question.我们何时举行会议是个重要的问题。
Where I spend my summer is no business of yours.我在哪里过暑假不关你的事。
[名师点津]who 引导的主语从句表示一件“事情”，表示特指；而whoever 引导的主语从句指“人”，表示泛指。
Who will go to the concert is not known.不知道谁会去听音乐会。
Whoever will go to the concert is welcome.无论谁去音乐会都会受到欢迎。
[名师点津]名词性从句引导词的确定步骤：(1)分析句式结构，明确名词性从句在句中的功能；(2)明确名词性从句所表达的意义；(3)明确名词性从句中所需要的成分及意义；(4)确定从句的引导词。
人教版高一英语必修三 unit3 Grammar 名词性从句-宾语从句和表语从句课件
• 1.The trouble is ______ I have lost his addrtehsast . • 2.The reason ____ he was late was ____ he missed the first bus this morning. • 3.His proposal was that we _________ (collect)all the related information.
注意
demand, order, suggest, advise, insist, desire, request, propose, command 等表示“要求、命令、建议、决定”等动词后接宾语从句时，宾 从的谓语用 “(should+)动词原形”，表示虚拟语气。
Observation（two） lI would appreciate if you would like to teaict h me how to use the computer. lI hate when thitey talk with their mouths full of food.
介词+宾语从句
l I lived in what you call “Ancient Greece”.
summary
介词 + whether + 陈述句 介词 + wh-词 + 陈述句
注意注意
l 宾语从句的时态必须与主句呼应： 1）主句—现在或将来时态，宾从—根据需要使用任何时态 2）主句—过去时态, 宾从—过去时态 【例外】: 主句—过去时态，宾从—一般现在时态 (宾从表示的是客观事实、自然现象或真理时)
人教版高中英语Book2 Unit 3 computers grammar 定语从句教学课件 (共34张PPT)
her.
A. what B. why C. when D. which She gives the reason for not coming to the
party.
33
Thank you!
34
《小芳》
There is a beautiful
村里有个姑娘叫小 and kind girl named
芳
Xiaofang in the
长得好看又善良 village.
一双美丽的大眼睛wShoe has a pair of
辫子粗又长
beautiful big eyes
在回城之前的那个 and long thick hair.
much/little + that (no/little/few/any)+先行词+that
20
1. The man and the horse C__fell into
the river were drowned(淹死).
A. which B. who
C. that
D. of which
2. There is nothing in the world _A_ can
the party?
Almost, but I don’t know the one
with _ you talked.
A. who, who B. which, which
C. that, whom D. who, that
22
关系副词when, where, why
关系副词 先行词 在从句中的成分
3
主句、从句、先行词、关系代词
A person (who loses wealth) loses much;
高中英语必修2module3 grammar 课件
China.
A. that B. when C. since D. as ④ It was for this reason ___C_____ her uncle moved out of New York and settled down in a small village. (Shanghai
主语 从句
强调句型
1.It _____ Mike and Mary who helped the
old man several days ago .
A. was
B. are
C. were
D. had been
2. Our classroom is very clean. Do you
know who ＿＿ cleaned it﹖
④ 当强调not…until结构时，必须将 not until连用,后面接肯定式。
I didn’t realize what trouble he was in until at that time.
It was not until at that time that I realized what trouble he was in.
He does work hard and finish the job in time. 2.在肯定的祈使句中，用动词do来加强语气，可译成“务必，一 定，千万〞 (24)Do come and see us some day. (25)Do give her my regards.
用助动词帮助强调
人教版选择性必修二SectionⅢGrammar——表语从句
⼈教版选择性必修⼆SectionⅢGrammar——表语从句Section ⅢGrammar——表语从句⼀、定义[合作探究]This is where I don’t agree with you.(where引导表语从句，where在从句中作地点状语)这就是我不同意你的地⽅。
That is why he was late for class again.(why引导表语从句，why在从句中作原因状语)那就是他⼜⼀次上课迟到的原因。
My question is where we will travel and how we will get there.(where引导表语从句，where在从句中作地点状语；how引导表语从句，how在从句中作⽅式状语)我的问题是我们将去哪⼉旅⾏以及我们将如何到达那⾥。
[⾃主发现1]在主从复合句中充当表语的从句，其作⽤相当于⼀个名词。
表语从句放在系动词之后，即主语＋系动词＋表语。
⼆、⼏种表语从句1.that与what引导的表语从句[合作探究]The trouble is that I have lost his address.⿇烦是我把他的地址丢了。
That was what she did this morning on her way to school.那就是她今天早晨在去学校的路上做过的事。
[⾃主发现2]连接词that引导表语从句，不充当成分，⽆意义，但是不能省略；what是连接代词，引导表语从句时，在从句中作主语、宾语、表语或定语。
2.whether引导的表语从句[合作探究]The question is whether you can do the work well.问题是你能否做好这项⼯作。
[⾃主发现3]whether引导表语从句，不充当成分，意为“是否”。
此时⼀般不能与if互换。
3.why与because引导的表语从句[合作探究]The reason why he asked for two days’ leave is that he had to take care of his sick son.他请了两天假的原因是他要照顾他⽣病的⼉⼦。
2020-2021学年英语人教版必修2课件：Unit 2 Section Ⅲ Grammar
5．are taken 句意：要是不采取一些措施，这条河将受到 进一步污染。主句为一般将来时，unless 引导的条件状语从句通 常用一般现在时表示将来，且 measures 与 take 之间是被动关 系，故用一般现在时的被动语态。
3．篮球运动需要合作，我既要明白队友的举动也要让队友 知道我的需要；
4．5 年的打球经历让我交到了很多朋友，我很喜欢同朋友 们一起打篮球。
注意：可适当增加细节，以使行文连贯。 参考词汇：合作 cooperation; 队友 teammate
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高三英语二轮复习表语从句课件12张PPT
1、（
）We decide our favorite basketball stars according to their on-court performance
and this is ______ Kobe Bryant has such a large fan base.
【选项】A． because
【选项】A．what
B．that
9
{
}From space, the earth looks blue. This is
about seventy-one
percent of its surface is covered by water.
【选项】A．why
B．how
C．because
D．whether
often blame for their lack of sleep.
【选项】A．what
B．that
C．which
D．why
（
）
【题目】The strange thing about Nicholas is _____ he taught himself to read
before he could speak.
C．that; whatever D．when; what
【题目】One of the glorious moments in my school life was _____ I was
awarded the Mayor’s Award.
【选项】A．why
B．how
C．that
D．when
8
（
）【题目】According to a survey, homework is_____ students most
高中英语人教版选修性必修二Unit 1—Unit 3语法知识讲解
高中英语选必二语法知识讲解Unit 1 Science and Scientists表语从句一、定义表语从句是复合句中的一种结构，它充当表语的角色。
表语本身也是一个句子，那么这个句子就被称为表语从句。
表语从句通常位于主句的系动词之后，用来解释和说明主语，从而使主语的内容更加具体化。
表语的作用是描述主语的身份、性质、品性、特征和状态。
表语可以由名词、形容词、副词、介词短语、不定式、动词的-ing形式以及从句来充当。
通常，表语位于系动词（如be, become, appear, seem, look, sound, feel, get, smell等）之后。
二、结构“主语+系动词+表语从句(引导词+其他)”表语从句也必须用陈述语序。
系动词分类：be（状态系动词）keep, remain, stay, lie, stand（持续系动词）seem, appear, look（表像系动词）feel, smell, sound, taste, look（感官系动词）become, grow, turn, fall, get, go, come（变化系动词）三、连接词从属连词、连接代词和连接副词、其他。
四、用法1.从属连词: that& whether（1）that引导表语从句时，只起连接作用，不作句子成分，有/没有意义，不能省略。
（2）whether引导表语从句时，只起连接作用，不作句子成分，通常翻译为“是否”。
引导表语从句时不能用if替换whether。
2.连接代词: who, whom, whose, which, what, whatever, whoever, whichever等连接代词引导表语从句时，既起连接作用，又作句子成分：主语、宾语、表语等3.连接副词：when, where, why, how, whenever, wherever等连接副词引导表语从句时，既起连接作用，又作句子成分：状语。
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Section Ⅲ Grammar —表语从句和主语从句语法图解探究发现①My feeling is that they're going to be big one day.②But the big surprise of the evening was when I was elected prom queen!③China is no longer what it used to be.④The reason why I'm calling you is that I want to invite you to my birthday party.⑤That she has became an artist may have been due to her father's influence.⑥What we should do next remains unknown.⑦Whether it will do us harm remains to be seen.⑧It's a good thing that the exams are finished.[我的发现](1)以上句中，①～④句中黑体部分均引导表语从句，而⑤～⑧句中黑体部分则引导主语从句。
(2)由④句可知，主语为名词reason时，表语从句中的连接词要用that，而不用why。
(3)由⑤⑥句知，引导主语从句时，what要在从句中充当句子成分，而that不作任何成分，只在语法上起连接作用。
(4)⑧句中，it用作形式主语，代替that引导的主语从句。
一、表语从句1．定义在复合句中作表语的从句，叫作表语从句。
它位于主句的系动词之后，对主语进行解释、说明，使主语的内容具体化。
2．引导词[即时演练1] 用适当的连接词填空①My opinion is that we should communicate with parents frequently.②The problem is whether we can find them there.③This is what I should have done first of all.④This is where I don't agree with you.⑤The question is how we can get in touch with him.⑥The problem is who will come to replace her.⑦This is because it is raining outside.3．注意事项(1)that与what的区别that引导表语从句时，是连词，在从句中不作成分；what是连接代词，引导表语从句时，在从句中作主语、宾语、表语或定语。
That was what she did this morning on her way to school.那就是她今天早晨在去学校的路上做过的事。
(2)because与why的区别because引导表语从句时强调原因，why引导表语从句时强调结果。
She often comes late.That's because she has a baby to take care of.她经常迟到。
那是因为她有一个孩子要照顾。
She has a baby to take care of.That's why she often comes late.她有一个孩子要照顾。
那就是她经常迟到的原因。
[名师点津] 名词reason作主语时，后面的表语从句表示原因时要用that引导，而不用because。
The reason why he was late is that it was raining hard.他来晚了是因为天正下大雨。
[即时演练2] 用that/what/because/why填空①(2016·北京高考改编)The most pleasant thing of the rainy season is that one can be entirely free from dust.②This was what he told me.③My belief is that I will succeed by working hard.④I had neither a raincoat nor an umbrella.That is why I got wet through.⑤You always make the same mistakes in the exams.I think that is because you are too nervous.(3)虚拟语气用于表语从句①在表示建议、劝告、命令等含义的名词后的表语从句中，谓语动词用“should＋动词原形”，should可以省略。
My suggestion is that we (should) have a discussion about this matter instead of just laying it aside.我的建议是我们应当讨论一下这件事，而不应该只是把它放在一边。
②as if/as though引导的表语从句常用虚拟语气。
用一般过去时表示现在，过去进行时表示现在进行，过去完成时表示过去，could/would/might＋动词原形表示将来。
It looks as if he were ten years younger today.今天他看起来好像年轻了10岁。
[即时演练3] 用所给词的适当形式填空①The doctor's advice is that we (should) take (take)more exercise.②The proposal is that the school (should) enlarge (enlarge) the playground.二、主语从句(一)主语从句的引导词连接词：that, if, whether；连接代词：what, who, whom, which, whose, whatever, whoever, whichever, whomever；连接副词：when, where, how, why等。
It is very important whether we can finish that task on time.我们能否按时完成任务很重要。
It is certain that the film Wolf WarriorⅡ was a success.可以肯定的是电影《战狼Ⅱ》是一部成功的影片。
Whichever of you comes in will receive a prize.你们当中不论哪个进来都将得到奖品。
[名师点津] whether/if在从句中不充当句子成分，起连接作用，意为“是否”。
whether引导的主语从句既可放在句首，也可放在句尾；if引导的主语从句只能放在句尾，前面用it作形式主语。
如果whether引导的主语从句用it作形式主语，whether可换成if。
Whether life exists on other planets is not clear.其他星球上是否存在生命还不清楚。
It is doubtful whether/if she would play the role.她是否要演这个角色还很难说。
[即时演练4] 完成句子①Whether he'll come here isn't clear.他是否会来这里还不清楚。
②That the earth turns around the sun is known to all.我们都知道地球围着太阳转。
③What will happen to the world is difficult to predict.世界将发生什么事情是难以预测的。
④Who will win the match is still unknown.谁能赢得这场比赛还不得而知。
⑤Why he gave up the chance of studying abroad is unknown.他为什么放弃了出国学习的机会还不清楚。
(二)注意事项1．常用it作形式主语的句型(1)It＋be＋形容词(obvious, true, natural, surprising, good, wonderful, funny, certain等)＋that从句It is wonderful that all of you have passed the difficult exam.你们都通过了这么难的考试，真是太好了。
[名师点津] 在“It＋be＋形容词＋that从句”句型中，如果形容词为necessary, important, strange, natural等时，从句谓语动词常用“(should＋)动词原形”。
It is important that we (should) build more hydroelectric power stations.我们建立更多的水力发电站是重要的。
(2)It＋be＋名词词组(no wonder, an honour, a good thing, a pity, no surprise, etc.)＋that从句It is no wonder that she was so upset.难怪她如此心烦意乱。
(3)It＋be＋过去分词(said, reported, thought, expected, decided, announced, arranged, etc.)＋that从句It's reported that another earth satellite has been put into orbit.据报道另一地球卫星已被送入轨道。
[名师点津] 在“It＋be＋过去分词＋that从句”句型中，如果过去分词为suggested, advised, ordered, requested, required等时，that从句谓语动词使用“(should＋)动词原形”。
It is suggested that you (should) attend the opening ceremony.有人建议你出席开幕典礼。
(4)It seems/happens等不及物动词或短语＋that从句It seems that they have known our secret.好像他们已经知道了我们的秘密。