外研版（2019）选择性必修 第二册Unit 4 Breaking boundaries Using language课件（12张ppt）
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| 名称 | 外研版（2019）选择性必修 第二册Unit 4 Breaking boundaries Using language课件（12张ppt） |  | |
| 格式 | pptx | ||
| 文件大小 | 197.0KB | ||
| 资源类型 | 教案 | ||
| 版本资源 | 外研版（2019） | ||
| 科目 | 英语 | ||
| 更新时间 | 2022-12-29 21:24:58 | ||
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(共12张PPT)
UNIT 4 Breaking boundaries
Using language
it 作形式主语
[观察例句]1．It is difficult for a foreigner to learn Chinese.2．It's kind of you to help me.3．It is no use talking to him about it.4．It is a mystery to me how it all happened.5．It is believed that the flood there is the biggest in 100 years.
[归纳用法]it作形式主语时没有具体的意义，只是帮助把真正的主语移到句子后面去，使句子显得平衡。it作形式主语时，真正的主语通常是不定式短语、 ing短语或主语从句。
一、不定式短语作真正的主语，常用于下列句型中：
It ＋ be ＋形容词 ＋ (for/of sb.) to do sth.
It ＋ be ＋ 名词 ＋ to do sth.
It takes sb.some time to do sth.干……花了某人……时间
It's up to sb.to do sth.干……是某人的职责或义务
It is everyone's duty to obey the law.
遵守法律是每个人的义务。
It took them a year to build the bridge.
建这座桥花了他们一年的时间。
It is bad manners to stare at people.
盯着人看是不礼貌的。
It is up to us to help those in need.
帮助那些有困难的人是我们的责任。
[名师点津]
在“It＋be＋形容词＋for/of sb.to do sth.”句型中，如果形容词描述的是sb.，则应用介词of；如果描述的是to do sth.就用for。
It's necessary for us to use a short wave radio to pick up the programmes.
我们用一台短波收音机收听这些节目是必要的。
It was foolish of him to give up the job.
他放弃那工作是愚蠢的。
[即学即练1] 用所给词的适当形式填空
①It is not up to you _________(tell) me how to do my job.
②It is not right _________(use) these places as rubbish dumps.
③It was nice of them __________(invite) us.
to tell
to use
to invite
二、 ing短语作真正主语的情况远不及不定式短语那么普遍，常限于no good, no use, useless, waste等词的后面。
It is no good/ use having a car if you can't drive.有车如果不会开是没有用处的。It is a waste of time watching TV.看电视是浪费时间的。 It is no use asking him.问他没有用。
[即学即练2] 用所给词的适当形式填空
①It's no good _________(take) over the experience of foreign countries uncritically.
②It's no use ________(cry) over spilt milk.
③It is worth ________(make) an appointment before you go.
taking
crying
making
三、用it作形式主语，主语从句作真正主语的常见句型有：
1．It is a pity/ a shame/ a fact/ an honour/ good news/ no wonder/ a wonder... that...
It was a pity that the engineer couldn't come.
可惜工程师没能来。
2．It is ＋ 形容词(如： strange/ natural/ surprising/ obvious/ true/ fortunate/ wonderful/ funny/ possible/ impossible/ likely/ unlikely/ clear/ unusual/ certain/ important...)＋that...
It is certain that he will win.
他一定会取胜。
3．It seems/ happened/ turned out/ suddenly struck me/ occurred to me...that ...
It happened that I wasn't there that day.
恰好那天我不在那里。
4．It ＋ be ＋ 过去分词(如：said/ reported/ announced/ decided/ expected/ hoped/ known/ believed...)＋that...
It is reported that more than twenty people were killed in that bus accident.
据报道在那次的公共汽车事故中有二十多人丧生。
【温馨提示】
It is suggested/required/desired/ordered/proposed...that sb. (should) do
It is necessary/ important/ strange/ natural/ essential/ urgent/right...that sb. (should) do
It is requested that he give a performance at the party.有人请求他在聚会上表演一个节目。
It is ordered that the radio be sent there at once.
据命令,这台收音机要立刻送到那里去。
[即学即练3] 用适当的代词填空
①It is known _______ he is one of the best teachers in our school.
②It suddenly occurred to me ________ I knew how to solve that problem.
③It is strange _______ he should have left without telling us.
that
that
that
单句语法填空1．It is very kind of you __________(give) me a hand in time.2．It is still a mystery ________ caused the accident.3．It is necessary that one _________(master) the skills of operating computer.4．It is known to all _______ the gun powder was first invented by the Chinese.5．It seemed certain _________he will win the prize.
to give
what
master
that
that
UNIT 4 Breaking boundaries
Using language
it 作形式主语
[观察例句]1．It is difficult for a foreigner to learn Chinese.2．It's kind of you to help me.3．It is no use talking to him about it.4．It is a mystery to me how it all happened.5．It is believed that the flood there is the biggest in 100 years.
[归纳用法]it作形式主语时没有具体的意义，只是帮助把真正的主语移到句子后面去，使句子显得平衡。it作形式主语时，真正的主语通常是不定式短语、 ing短语或主语从句。
一、不定式短语作真正的主语，常用于下列句型中：
It ＋ be ＋形容词 ＋ (for/of sb.) to do sth.
It ＋ be ＋ 名词 ＋ to do sth.
It takes sb.some time to do sth.干……花了某人……时间
It's up to sb.to do sth.干……是某人的职责或义务
It is everyone's duty to obey the law.
遵守法律是每个人的义务。
It took them a year to build the bridge.
建这座桥花了他们一年的时间。
It is bad manners to stare at people.
盯着人看是不礼貌的。
It is up to us to help those in need.
帮助那些有困难的人是我们的责任。
[名师点津]
在“It＋be＋形容词＋for/of sb.to do sth.”句型中，如果形容词描述的是sb.，则应用介词of；如果描述的是to do sth.就用for。
It's necessary for us to use a short wave radio to pick up the programmes.
我们用一台短波收音机收听这些节目是必要的。
It was foolish of him to give up the job.
他放弃那工作是愚蠢的。
[即学即练1] 用所给词的适当形式填空
①It is not up to you _________(tell) me how to do my job.
②It is not right _________(use) these places as rubbish dumps.
③It was nice of them __________(invite) us.
to tell
to use
to invite
二、 ing短语作真正主语的情况远不及不定式短语那么普遍，常限于no good, no use, useless, waste等词的后面。
It is no good/ use having a car if you can't drive.有车如果不会开是没有用处的。It is a waste of time watching TV.看电视是浪费时间的。 It is no use asking him.问他没有用。
[即学即练2] 用所给词的适当形式填空
①It's no good _________(take) over the experience of foreign countries uncritically.
②It's no use ________(cry) over spilt milk.
③It is worth ________(make) an appointment before you go.
taking
crying
making
三、用it作形式主语，主语从句作真正主语的常见句型有：
1．It is a pity/ a shame/ a fact/ an honour/ good news/ no wonder/ a wonder... that...
It was a pity that the engineer couldn't come.
可惜工程师没能来。
2．It is ＋ 形容词(如： strange/ natural/ surprising/ obvious/ true/ fortunate/ wonderful/ funny/ possible/ impossible/ likely/ unlikely/ clear/ unusual/ certain/ important...)＋that...
It is certain that he will win.
他一定会取胜。
3．It seems/ happened/ turned out/ suddenly struck me/ occurred to me...that ...
It happened that I wasn't there that day.
恰好那天我不在那里。
4．It ＋ be ＋ 过去分词(如：said/ reported/ announced/ decided/ expected/ hoped/ known/ believed...)＋that...
It is reported that more than twenty people were killed in that bus accident.
据报道在那次的公共汽车事故中有二十多人丧生。
【温馨提示】
It is suggested/required/desired/ordered/proposed...that sb. (should) do
It is necessary/ important/ strange/ natural/ essential/ urgent/right...that sb. (should) do
It is requested that he give a performance at the party.有人请求他在聚会上表演一个节目。
It is ordered that the radio be sent there at once.
据命令,这台收音机要立刻送到那里去。
[即学即练3] 用适当的代词填空
①It is known _______ he is one of the best teachers in our school.
②It suddenly occurred to me ________ I knew how to solve that problem.
③It is strange _______ he should have left without telling us.
that
that
that
单句语法填空1．It is very kind of you __________(give) me a hand in time.2．It is still a mystery ________ caused the accident.3．It is necessary that one _________(master) the skills of operating computer.4．It is known to all _______ the gun powder was first invented by the Chinese.5．It seemed certain _________he will win the prize.
to give
what
master
that
that