Unit4 Breaking boundaries Using language Grammar 课件-2025-2026学年高中英语外研版选择性必修第二册

Activate and share [ˈæktɪveɪt]激活与分享 What have we learnt about it ? 1.I dropped my watch and it broke. 2.There is a knock on the door. It must be the postman. 3.What’s this? It’s a new machine. something 某物 somebody 某人 pronoun [ˈprəʊnaʊn] 代词 It as an empty subject 2. it作形式主语的三种情况 2) 代表动名词 一般以“be + 名词”作谓语，也可以以“be + 形容词”作谓语。 It is no use doing that. It is pleasant sitting here. 3) 代表从句 具体又可以分为四种类型： ① it + be + 形容词 + 从句 她知道关于那件事的一切是很自然的事情。 It is natural that she knows everything about it. 2 4. It is Friday today. 5. It was very cold last Monday. 6. It lies in the south of Anhui. 7. It is about 8:30 now. 8. It is about 25km from my city to the capital. 9. It is 39 degrees! You got a high fever! Activate and share [ˈæktɪveɪt]激活与分享 What have we learnt about it ? date 日期 wether 天气 place 地方 time 时间 distance 距离 temperature温度，体温 Look at the sentences and answer the questions. Sentences (a) and (c) are from the reading passage. (P54) Q1. What does “it” refer to in sentences (a) and (c)? a But it is vital not to take any chances. b But not to take any chances is vital. c It is important to remember that Ebola doesn’t respect national boundaries. d To remember that Ebola doesn’t respect national boundaries is important. “It” refers to “not to take any chances” in sentence (a). “It” refers to “to remember that Ebola doesn’t respect national boundaries” in sentence (c). Q2. What is the difference between the sentences in each group? a But it is vital not to take any chances. b But not to take any chances is vital. c It is important to remember that Ebola doesn’t respect national boundaries. d To remember that Ebola doesn’t respect national boundaries is important. The first sentences in each group use “it” as an empty subject at the beginning of the sentences. 形式主语 It as an empty subject It 作形式主语 通常it作为形式主语，在句中没有实际意义，只是满足语法需要，起到一个平衡句子结构，避免句子头重脚轻的作用。 概念 由于主语过长,为了避免头重脚轻,常常用it作形式主语,而把真正的主语放在后面。 it作为形式主语主要分为三种情况。 类型 1. 代表不定式 (1) It + be + 形容词 + 不定式 It is difficult to translate the book. (2) It + be + 名词 + 不定式 It was her duty to clean the room. (3) It + be + 介词短语 + 不定式 It was against my principle to do that. (4) It + 及物动词 + 宾语 + 不定式 It cost 150 yuan to buy the dress. 翻译这本书很难。 打扫房间是她的职责。 那样做违反了我的原则。 买这件衣服花了150元 语境运用 完成句子 ①开车的时候一直系着安全带是非常重要的。 　　　 　　　 　 to always wear a safety belt when you’re driving.  ②在周六早上出去散步是她的习惯。 　　　　 　　　　 to go for a walk on Saturday morning.  ③成千上万的人花了十年的时间建造了这座宫殿。 It took thousands of people ten years 　　　　　　　　 　.  It is essential It is her custom to build the palace 类型 2. 代表动名词 it 代表动名词时，一般以“be + 名词”作谓语，也可以以“be + 形容词”作谓语。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. It is a waste of time watching TV It is no use asking him. 语境运用 完成句子 ①熬夜没有好处。 It’s no good 　　　　　　　　.  ②到陌生的地方游玩真是有意思。 It is fun 　　　　　　　　　.  staying up late visiting new places 类型 3. 代表从句 It + be + ……从句，具体可以分为四种类型： （1）it + be + 形容词 + 从句 It is clear that he told a lie. （2）it + be + 名词 + 从句 It is a pity that you can't come. （3）it + 动词的被动语态 + 从句 It is said that he is friendly. （4）it + be/其他系动词 + 从句 It may seem that you’re wasting your life away. It as an empty subject It 作形式主语 句型 It is clear / obvious / true / possible / certain / … that… It is important / necessary/ right / strange / natural / …that… (should) do… It is said / reported / learnt / …that… It is suggested / ordered / required /…that... (should) do... It is a pity / shame / …that… It happens / seems / looks /appears /…that… It was surprising that she passed the difficult exam. 真让人惊讶,她居然通过了这次有难度的考试。 此句中,it为形式主语,真正的主语为that引导的从句“that she passed the difficult exam”。 It is clear that he told a lie. 很明显,他撒谎了。 此句中,it为形式主语,真正的主语为that引导的从句“that he told a lie”。 (2)It+be+过去分词(said/reported/believed/thought/expected/announced/confirmed/...)+that从句。 It’s said that they are opposite-sex twins. 听说他们是龙凤胎。 此句中,it为形式主语,真正的主语为that引导的从句。 (3)It+be+名词(a pity/no wonder/an honour/a good idea/a fact/ good news/...)+that从句。 It is no wonder that you didn’t pass the exam. 难怪你没有通过考试。 此句中,it为形式主语,真正的主语为that引导的从句。 (4)It+不及物 (短语)动词(seem/happen/appear/look/occur/turn out/...)+that从句。 It happened that they were out that day. 碰巧那天他们不在家。 (5)It+及物动词(worry/shock/...)(+sb/sth)+that从句。 It shocks me that he failed this exam. 他没有通过这次考试,这使我感到震惊。 此句中,从句用的是一般过去时,说明考试失利这件事发生在过去,it后的谓语动词用的是一般现在时,说明“我”知道他考试失利这件事发生在现在。it为形式主语,真正的主语为that引导的从句。 温馨提示 ①使用suggested、advised、required、requested、insisted、ordered等表示建议、要求、命令等含义的词时,从句应该用虚拟语气,其谓语动词为(should+)动词原形。 It’s suggested that students (should) make their beds by themselves. 有人建议学生应该自己铺床。 suggested表示建议,后面通常使用虚拟语气,其中should可以省略。it为该句的形式主语,真正的主语为that引导的从句。 ②当表语或宾语也为从句时,不能用it作形式主语。 A.What moved me is that they devoted the rest of their lives to scientific investigation. 让我感动的是他们将自己的余生献给了科学研究事业。 因为该句中that引导的从句位于系动词is的后面,为表语从句,所以此时不用it作形式主语。what引导的从句为句子真正的主语,且在该句中位于句首。 B.That I come here means that he has invited me. 我来这里就表明他已经邀请过我了。 第一个that引导的从句是句子真正的主语,此时不能用it作形式主语。第二个that引导的从句位于谓语动词means的后面,充当宾语,属于宾语从句。 It as an empty subject It 作形式主语 句型 It + be + adj. + of sb + to do… It + be + adj. + for sb + to do ① It is kind of you to think so much of us. ② It's nice of you to help me. ③ It's dangerous for us to swim in such deep pool. ④ It's necessary for us to study hard. 形容词为描述人品质及性格特征的词。常用的形容词有clever/ foolish/good/ nice/polite/kind等。 形容词为描述事物特征的词，常用的形容词有difficult / important / easy / hard/ necessary/ impossible/ dangerous等。  用法  类型 it作为形式主语，代替句子的逻辑主语，并无实际词义。这可以保持句子的结构平衡，避免主语太长，显得头重脚轻。 it作形式主语 It指代不定式 It指代动名词 It指代从句 真题体验 1.(2023·浙江1月卷)A few days later,I came back with my first jars of zero waste groceries,and my dad commented on how silly 　　　　 was for me to carry jars everywhere.  2.(2023·浙江1月卷)But no matter when you travel,it’s a good idea 　　　 　 (make) your reservations at least 90 days in advance.  it to make 1.it　此处的it是形式主语,真正的主语是to carry jars everywhere。本题考查“It + be +形容词+不定式”结构。故填it。 2.to make　此处的it是形式主语,真正的主语是to make your reservations at least 90 days in advance。本题考查“It + be +名词+不定式”结构。故填to make。 3.(2023·浙江1月卷)If 　　 　 takes the train 53 seconds to travel one mile,you’re going 67.92 mph.  4.(2023·新高考全国Ⅱ卷)It 　 　　　 (announce) that my train would arrive in 10 minutes.  5.(2023·新高考全国Ⅱ卷)It just 　　 　　 (happen) that I was planning another PNP flight with another pilot,Karen,who offered to take Tiffy from Kansas City to Virginia.  it was announced happened 3.it　此处的it是形式主语,真正的主语是to travel one mile。本题考查“It +及物动词+宾语+不定式”结构。故填it。 4.was announced　此处的it是形式主语,真正的主语是that my train would arrive in 10 minutes。本题考查“It+be+过去分词+that从句”结构。故填was announced。 5.happened　此处的it是形式主语,真正的主语是“that I was planning...to Virginia”。本题考查“It+不及物动词+that从句”结构。故填happened。 6.(2023·新高考全国Ⅱ卷)　　　　 has been an honour to watch the panda programme develop and to see the pandas settle into their new home.  7.(2023·全国乙卷)As 　　　　 turned out,Douglas did exactly what she needed to do to become Olympic champion when she defeated two Russians.  It it 6.It　此处的it是形式主语,真正的主语是“to watch...their new home”。本题考查“It + be +名词+不定式”结构。故填It。 7.it　As it turned out在句中为非限制性定语从句,其中it为形式主语,指代as所指代的成分,as指代后面的主句“Douglas did exactly what...defeated two Russians”。故填it。 语法专项训练 Ⅰ.句子语法填空 1.As far as I’m concerned,it’s necessary 　　　　 (have) a good command of English.  2.It was really very kind of you 　　 　　 (give) me a lift home.  3.It is useless 　　 　　 (wait) here doing nothing.  4.It hit me all of a sudden 　　　　 I had forgotten her birthday.  5.With little or no previous experience,　　　　 is no wonder that you always make mistakes.  to have to give waiting that it Ⅰ. 用适当的内容或括号中所给单词的适当形式填空。 1. It is impossible ______ (get) there by boat. 2. They are good friends. ______ is no wonder that they know each other very well. 3. _____ is a fact that English is being accepted as an international language. 4. It seemed ________ he didn’t tell the truth. 5. It took the workers almost three years ________ (build) the station. 6. It is uncertain __________ he can come to Jenny’s birthday party. to get It It that to build whether It is known to us _______ the mobile phone plays a very important part in our life and work. Is it possible for us ________ (live) without it? Perhaps the answer is NO. ____ is a habit for most people _______ (turn) on their smart phones and surf the Internet as soon as they wake up. And it seems _______ there is something important waiting for them to deal with. What’s more, some people spend all day playing games on the phone. We know it is difficult for them _______ (beat) their addiction. So ____ is our duty to call on the public to reduce the time they spend on the phone. Ⅱ. 用适当的内容或括号中所给单词的适当形式，完成短文。 that to live It to beat it that to turn Ⅱ.完成句子 1.很遗憾你错过了这次宝贵的机会。 　　　　　　　　 you miss the invaluable opportunity.  2.似乎每个人都想为庆典做些什么。 　　　　　　 everyone wants to do something for the celebration.  3.希望你慎重考虑一下这个事情,并且尽早给我们答复。 　　　　　　　　 you will seriously take this matter into consideration and give us a reply at your earliest convenience.  It is a pity that It seems that It is hoped that 4.鲸不是鱼,这是一个常识。 　　　　　　　　　　 that the whale is not a fish.  5.很明显,我们的国家正在变得越来越强大和富有。 　　　　　　 　 our country is becoming stronger and wealthier. It is a common sense It is obvious that Rewrite the underlined parts using it as an empty subject. it is no longer quite so difficult for women and minorities to get roles in American film and television it is now a more realistic hope for minority actors to become a leading actor in Hollywood it is more common than before for women to write and direct Hollywood films it is seen as acceptable by film studios to cast white actors as Asian characters Describe the city using the information provided and it as an empty subject. Beijing today is multicultural. It is not a surprising thing for students to see different skin colours in the same class. It is possible for people to hear many different languages and dialects. It is easy for people to find products from all over the world. It is not difficult for foreigners to settle down and find a job. It is a common thing for people from different countries to work in the same company. Task 4: Describe one of the cities using it as an empty subject where appropriate. Do online research if necessary. (P55) Lavf58.45.100 $