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

该高中英语学案聚焦“It作形式主语”核心知识点，通过课前复习It的基本用法（如指代事物、指人、表天气及形式宾语等）搭建学习支架，引导学生从已知过渡到形式主语的深入探究，梳理前后知识脉络。 资料亮点在于通过观察对比句子培养思维品质，结合语境运用与高考真题提升语言能力和学习能力，习题从基础训练到真题体验层次分明，帮助学生巩固应用，有效提升课堂学习效率与语法运用能力。

班级: 姓名: Topic：XB2 U4 Breaking boundary Type of lesson：Using language-- It作形式主语 【课前复习】 Ⅰ. 复习It 的基本用法：代词it既是宾格又可以做主格，有时也可以指人。 1　 My pen is missing. I can’t find it anywhere. 指代 2　 —Who is knocking at the door? —It is me. 指 3　 The woman had a baby. It was five months old. 表示 4　 It will be sunny tomorrow. 表示 5　 I found it difficult to learn English well first. 作形式 6　 It is impossible for us to learn Japanese. 作形式 【课中学习】 Ⅱ. 观察与思考: 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. 1. What does “it” refer to in sentences (a) and (c)? 答：____________________________________________________ 2. What is the difference between the sentences in each group? Why does the author choose to use sentences (a) and (c) instead of (b) and (d)? 答：___________________________________________________ · 总结：“It”可以放在主语位置，用来代替_______________，作形式主语。 Ⅲ. It 作形式主语的用法（核心考点） 为避免主语过长、头重脚轻，用it作形式主语放在句首，真正主语后置。真正主语可以是：不定式、动名词、that 从句。 语法知识点拨 (一) It 代表不定式 1　 It + be +形容词+不定式 例：It is difficult to finish this job. 很难完成这项工作。 2　 It + be +名词+不定式 例：It was my duty to keep the meeting room clean. 保持会议室干净是我的职责。 3　 It +be +介词短语+不定式 例：It was beyond my ability to repair the machine.修好这台机器不在我的能力范围之内。 4　 It +及物动词+宾语+不定式 例：It takes a lot of stamina to run a marathon. 跑马拉松需要很大的耐力。 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。 2. _____________________ to always wear a safety belt when you’re driving. 3. 在周六早上出去散步是她的习惯。_____________________ to go for a walk on Saturday morning. 4. 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 _____________________. (二) It代表动名词 1　 It + be +名词+动名词 例：It is no use doing that. 那样做没有用。 2　 It + be +形容词+动名词 例：It’s worth reading this book. 这本书值得一读。 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 _______________________. (三) It代表that主语从句 1　 It +be+形容词+that从句 例：It is clear that he told a lie. 很明显,他撒谎了。 2　 It + be +过去分词+that从句 例：It’s said that they are opposite-sex twins. 听说他们是龙凤胎。 3　 It + be +名词+that从句 例：It is no wonder that you didn’t pass the exam.难怪你没有通过考试。 4　 It +不及物(短语) 动词+ that从句 例：It happened that they were out that day. 碰巧那天他们不在家。 5　 It +及物动词(+sb/sth) + that从句 例：It shocks me that he failed this exam.他没有通过这次考试,这使我感到震惊。 语境运用（语法填空） 1. It’s a pity I didn’t think of it earlier. 2. Just then it （occur) to me that another opportunity was knocking. 3. It is universally acknowledged it’s very difficult to shake off bad habits. 4. It _________ (believe) that tea was brought to Korea and Japan during the 6th and 7th centuries. 5. It is necessary that food (send) to them at once. 6. It satisfied her mother she completed the performance perfectly. 【课后巩固】 Ⅳ、真题体验（高考真题） (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. (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. (2023・浙江1月卷) If ________ takes the train 53 seconds to travel one mile, you’re going 67.92 mph. (2023・新高考Ⅱ卷) It ________ (announce) that my train would arrive in 10 minutes. (2023・新高考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. (2023・全国乙卷) ________ has been an honour to watch the panda programme develop and to see the pandas settle into their new home. (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. Ⅴ、语法专项训练 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. 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. 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. Ⅵ. 课后小测 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. Ⅶ. 短文填空 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. 参考答案： Ⅰ、课前复习 1. 指代前文单数事物（my pen） 2. 指不明身份 / 敲门的人 3. 表示性别不明的婴儿 4. 表示天气 5. 作形式宾语 6. 作形式主语 Ⅱ、课中学习 1. It 指代后面的真正主语：不定式短语 / 不定式从句 2. 每组两句句意相同；(a)(c) 用 it 作形式主语，把真正主语后置，避免句子头重脚轻，句式更平衡、更自然流畅。总结：用来代替 不定式、动名词、that 从句 Ⅲ、语法知识点拨 语境运用 （一）It 代表不定式 完成句子 1. It is very important to always wear a safety belt when you’re driving. 2. It is her habit to go for a walk on Saturday morning. 3. It took thousands of people ten years to build the palace. （二）It 代表动名词 完成句子 1. It’s no good staying up late. 2. It is fun visiting strange places. （三）It 代表 that 从句 语法填空 1. that 2. occurred 3. that 4. is believed 5. (should) be sent 6. that Ⅳ、课后巩固 真题体验 1. it 2. to make 3. it 4. was announced 5. happened 6. It 7. it Ⅴ、语法专项训练 句子语法填空 1. to have 2. to give 3. waiting 4. that 5. it 完成句子 1. It’s a pity that 2. It seems that 3. It is hoped that 4. It is common sense 5. It is obvious that Ⅵ、课后小测 1. to get 2. It 3. It 4. that 5. to build 6. whether/if Ⅶ、短文填空 1. that 2. to live 3. It；to turn 4. that 5. to beat 6. it 1 学科网（北京）股份有限公司2 学科网（北京）股份有限公司 $