Unit 2 Period 3 Learning About Language 语法精析课（教用Word）-【金榜题名】2025-2026学年高二英语选择性必修第三册高中同步学案（人教版）

本高中英语讲义聚焦动词不定式作主语的核心语法点，系统梳理其基本用法（谓语用单数、it作形式主语、for/of复合结构）及与动名词作主语的异同，通过“读句感悟-语法精析-练习巩固”的学习支架，引导学生从实例感知到规则理解再到综合应用。 资料亮点在于以学生为中心的活动设计，如Activity 1通过例句让学生自主发现规律，提升语言能力中的理解能力，语法精析对比不定式与动名词，培养思维品质中的分析比较能力，多样化练习（单词拼写、语法填空、短语运用）助力语言表达，课中辅助教师高效教学，课后帮助学生巩固知识、弥补薄弱点。

Period 3　Learning About Language　语法精析课 素养目标 1．Understand how an infinitive is used as a subject and a predicative in a sentence. 2．Know how to distinguish the grammatical function of an infinitive in reading materials. 3．Make sure that you can get the right meaning of a sentence with infinitives. 4．Learn to use the infinitives to write simple sentences grammatically correct. Activity 1　读句感悟 阅读下列句子，认真感悟加黑部分，并完成方框下的小题。 (1)However，during this period，it can be easy for some of them to form bad habits. (2)To prevent harmful habits like these from dominating a teenager's life is essential. (3)To change bad habits is never easy，even with many attempts. (4)After all，it is not easy to break bad habits. 1．以上句子中动词不定式都是作主语。 2．句(1)和句(4)中it作形式主语，真正的主语是后面的动词不定式。 Activity 2　语法精析 一、基本用法 动词不定式作主语时，谓语动词用单数。 To look after these naughty boys is really difficult. 照看这些淘气的男孩真的很难。 为了避免头重脚轻，常用it作形式主语放在句首，作主语的不定式常置于句末。 It would be better for you to go there. 你还是去那里的好。 注意：1.若要说明不定式表示的动作的发出者，要在不定式前加for引起的短语，构成“for＋名词(或代词宾格)＋不定式”短语，这一短语被称为不定式的复合结构。 2．在“It is＋adj.＋不定式复合结构”句型中，当其中的形容词是说明逻辑主语的性质、品质时，要由of引出逻辑主语，不能用for。这类形容词主要有clever，foolish，kind，nice，polite，silly，stupid，wise等。 　It's very easy for him to work out this math problem. 对他来说解出这道数学题很容易。 It was careless of him to make such a mistake. ＝He was careless to make such a mistake. 犯了这样的错误，他太粗心了。 二、动词不定式和动名词作主语的异同点 1．动名词和不定式作主语的相同点 (1)不定式和动名词作主语时，常常为了保持句子的平衡，用it来作形式主语，如： It is not easy to learn English well. 学好英语不容易。 It is no use asking him for help. 向他求助是没有用的。 (2)如果主语用了不定式，表语和宾语也要用不定式；主语用了动名词，表语和宾语也要用动名词，这在英语中称为对称性，如： To see is to believe.＝Seeing is believing. 眼见为实。 It is better to stay home than to go out. 待在家里比出去要好。 2．动名词和不定式作主语的不同点 (1)不定式作主语常表示具体的某一动作；表示泛指或一般的抽象的概念时，多用动名词。 Walking is a good form of exercise for both the young and the old. 散步是一种老少皆宜的很好的运动形式。 (2)在“It＋be＋no use(good/help/need等)”之后常用动名词作主语，而少用不定式。 It is no use crying over the split milk. 覆水难收。 It is no help taking this medicine. 服用这种药没有用。 注意：如果该句型中用了for引出不定式的逻辑主语，就只能用不定式。 It is no good for us to do that exercise. 我们做那种练习没有好处。 (3)不定式可以和when，where，how，what，whether等连用，在句子中作主语、宾语和表语，而动名词则不能。 Where to put the box seems hard to decide. 很难决定把这个箱子放在哪里。 Whether to do it hasn't been decided. 是否做这件事还没定下来。 Ⅰ.单词拼写 1．He followed his father and became a surgeon (外科医生)． 2．I don't like myself without a beard (胡须)． 3．Shirley's brother is now a consultant (顾问) heart surgeon in Sweden. 4．He ignored all the“No Smoking”signs and lit up a cigarette (香烟)． 5．If you get up early, try not to disturb (打扰) everyone else. 6．The scene moved him to compose a poem. 7．He was examined again and then prescribed a different herbal medicine. 8．If your friend is being physically abused，you might have noticed bruises and scars. 9．Please don't shave off your beard without warning me.I'm so used to your face with it. 10. Physical activity is an important factor in maintaining fitness. Ⅱ.单句语法填空 1．He needed emergency surgery (surgeon) to remove a blood clot from his brain. 2．Before liberation (liberate) there were few doctors and little medicine in the countryside. 3．Doctors were disturbed (disturb) that less than 30 percent of the patients were recovered. 4．The specialist (special) who carried out the brain scan thought Tim's chances of survival were slim. 5．That company wanted to hire him as their consultant (consult)，but he declined firmly. 6．In order to stay healthy，he cut down on coffee and cigarettes (cigarette)，and ate a balanced diet. 7．Some people fear that technological changes will eventually lead to unemployment. 8．I was too nervous to_remember (remember) what I had said in the important speech. 9．I will lend her some money in reward for her timely help. 10．The young man rushed into the castle to rescue the boy dominated (dominate) by the group. Ⅲ.短语填空 cut out；make up one's mind；be composed of；take action；lose weight；take up；in response to；after all；shave off；stick to；skip through 1．I hated practicing playing the piano，but I stuck_to it and now I can play pretty well. 2．Smartphones not only take_up our valuable time，but also do great harm to our health. 3．The tailor carefully examined the cloth before starting to cut_out the garment. 4．I've made_up_my_mind，but it's obvious that you need more time to think. 5．The character“王” is_composed_of one vertical and three horizontal strokes. 6．It might be a good idea to shave_off your beard before going to Beijing for the interview. 7．We must take_action to deal with the problem before it spreads to other areas. 8．As I have taken these two simple steps to exercise，I started to lose_weight. 9．What will the new actor do in_response_to the funny news? 10．She skipped_through the boring bits of text and just looked at the pictures. 学科网（北京）股份有限公司 $