Unit 2 Healthy Lifestyle Discover useful structures导学案 2025-2026学年高中英语人教版选择性必修第三册

该高中英语导学案聚焦人教版选择性必修第三册Unit 2“Healthy Lifestyle”的“动词不定式作主语”语法点，通过引导学生观察教材例句、分析不定式位置及功能，结合改写句子活动，搭建从具体语境到语法规则的学习支架，衔接前后语法知识。 资料以“观察-探究-练习”为主线，深度探究主谓一致、it作形式主语等规则，融入健康生活主题练习，既提升语言能力（正确运用语法结构），又培养思维品质（分析比较不定式与动名词区别），通过疑问词+不定式拓展学习能力，助力学生自主构建语法体系。

人教版选择性必修第三册Unit 2 Healthy Lifestyle Discover useful structures（导学案） 1、 学习目标 1. 能够理解动词不定式作主语的功能和意义，并结合语境正确运用动词不定式作主语进行表达。 2. 进一步思考如何养成健康的生活方式。 2、 知识梳理----动词不定式作主语 （1） 观察例句，发现规则 1.观察教材17页Activity 1的四个句子，找出不定式位置以及功能。 （1） To change bad habits is never easy. （2） It took the surgeon three hours to finish my mother’s lung surgery. （3） To join the People’s Liberation Army, it is required for men to shave off their beards. （4） It was not polite to disturb your neighbours with loud music last night. 答案：句首，主语；句尾，主语；句首，主语；句尾，主语。 2.改写句子（教材17页Activity 1）。（to do在句首直接做主语和it作形式主语的转换。） 答案：（1）It is never easy to change bad habits. （2）To finish my mother’s lung surgery took the surgeon three hours. （3）To shave off their beards is required (for men). （4）To disturb your neighbours with loud music last night was not polite. （2） 深度探究，总结规则 探究一：主谓一致 例句：（1）To change bad habits is never easy. （1） To help others gives a person satisfaction. （2） To prevent harmful habits like these from dominating a teenager’s life is essential. Tip 1: 动词不定式作主语时，谓语动词常用______________________。 答案：单数 探究二：it作形式主语的常用句式 例句：（1）It took the surgeon three hours to finish my mother’s lung surgery. （2）To join the People’s Liberation Army, it is required for men to shave off their beards. （3）It was not polite (of you) to disturb your neighbours with loud music last night. （4）It is important to avoid passive cigarette smoking. （5）It will take a nutrition specialist an hour to make a balanced diet menu for you. （6）As a chef, it was my duty to cook, so I tried to vary the meals in whatever way I could. （7）It can be easy for some teenagers to form bad habits. Tip 2: Sentence patterns with “it” and infinitives as the subjects ① It + is/ was + ______________ + ______________ sb + to do ② It is/was + ______________ + to do ③ It + takes/ took/ will take sb. + __________________ + to do ④ It + is/ was ______________ + for sb + to do 答案：adj. for/of ; n. ; some time; v-ed. 探究三：for/of的选择 例句：（1）It is smart __________ you to turn to a fitness consultant for advice. （2） It is dangerous ____________ you to take illegal drugs. 答案：of; for Tip 3: 在 It + is/was + 形容词 + to do 的句式中, ① 当该形容词用以表示to do的特征时，使用 It is/was ＋ adj. ＋ ________ + sb. + to do； ② 当该形容词用来表示不定式的逻辑主语(sb.)的性质、特征或品德时，使用 It is/was ＋ adj. ＋ ________ + sb. + to do。 答案：for; of 探究四：to do as the subject VS doing as the subject Use the correct forms of the words to fill in the blanks. 例句：（1）__________________ (read) aloud is good for your English learning. （2）It is quite necessary __________________ (read) it again. （3）__________________ (see) is to believe. （4）__________________ (see) is believing. 答案：Reading; to read; To see; Seeing. Tip 4: 动词不定式和动名词作主语的区别： ____________作主语特指一次性的、具体的动作；____________作主语泛指一般的或习惯性的动作。 且作主语和表语的不定式或动名词需保持_____________。 答案：to do; doing; 一致 探究五：疑问词 + 不定式 分析例句中疑问词 + 不定式作什么成分。 例句：（1）When to start has not been decided yet. ____________________ （2）Do you know where to find Tom? ____________________ （3）My main concern is how to get there on time. ____________________ 答案：主语；宾语；表语。 Tip 5: 动词不定式可与疑问词when、where、how、what、which、who等组合，构成_______________________________，在句中可作______________、______________和______________。 答案：不定式短语；主语、宾语、表语。 3、 练习 1. 完成课本17页Activity 3 并回答How can we lose weight? 答案：be in control of; decide on; begin with; making choices; made up my mind. Do more exercises; drink more water; sleep enough. 2. 完成课本17页Activity 2. 答案：(1) It will take an hour for a nutrition specialist to make a balanced diet menu for you; (2) It is useful to turn to a fitness consultant for advice; (3) It is dangerous to take illegal drugs; (4) It is harmful to skip breakfast often. 3. 在文中找到更多的to do结构并分析其成分。 答案：例：After all, it is not easy to break bad habits; to break bad habits在句中做主语。 4. 完成下列练习题。 （1） 填空 （1） ____________________ (learn) a new language requires patience and practice. （2） It is necessary __________ us __________ (keep) a balanced diet to stay healthy. （3） It takes my sister 40 minutes __________ (walk) to school every morning. （4） ____________________ (solve) this problem is the most important task for our team today. （5） It is very kind __________ you __________ (offer) me such useful advice. （6） ____________________ (read) widely without thinking is not a good way to study. （7） The question is __________ to start the project—we haven’t decided yet. (用疑问词填空) （8） It is a great pleasure __________ (invite) to speak at your school’s English festival. （9） ____________________ (master) a skill well takes years of consistent effort. （10） It is dangerous __________ children __________ (play) with fire near the forest. （11） I don’t know __________ to choose between these two books. (用疑问词填空) （12） ____________________ (finish) all the homework in one hour is impossible for me today. （13） It is important __________ us __________ (develop) good learning habits as early as possible. （14） ____________________ (visit) the Great Wall has always been my biggest dream. （15） It took the workers three months __________ (build) the new library in our town. 答案：To learn · for; to keep · to walk · To solve · of; to offer · To read · when/how · to be invited · To master · for; to play · which · To finish · for; to develop · To visit · to build （2） 句型转换 （1） To learn a foreign language well is not easy.（用 it 作形式主语改写句子） （2） It is helpful for us to read more books.（改为同义句，用不定式作主语） （3） To finish the work in two days is a big challenge for him.（用 it 作形式主语改写句子） （4） We don’t know what we should do next.（改为 “疑问词 + 不定式” 结构） （5） It took her three hours to clean the house last Sunday.（改为同义句，用不定式作主语） 答案：· It is not easy to learn a foreign language well. · To read more books is helpful for us. · It is a big challenge for him to finish the work in two days. · We don’t know what to do next. · To clean the house took her three hours last Sunday. 1 / 7 学科网（北京）股份有限公司 学科网（北京）股份有限公司 $ 人教版选择性必修第三册Unit 2 Healthy Lifestyle Discover useful structures（导学案） 1、 学习目标 1. 能够理解动词不定式作主语的功能和意义，并结合语境正确运用动词不定式作主语进行表达。 2. 进一步思考如何养成健康的生活方式。 2、 知识梳理----动词不定式作主语 （1） 观察例句，发现规则 1. 观察教材17页Activity 1的四个句子，找出不定式位置以及功能。 （1） To change bad habits is never easy. （2） It took the surgeon three hours to finish my mother’s lung surgery. （3） To join the People’s Liberation Army, it is required for men to shave off their beards. （4） It was not polite to disturb your neighbours with loud music last night. 2. 改写句子（教材17页Activity 1）。（to do在句首直接做主语和it作形式主语的转换。） （1） （2） （3） （4） （2） 深度探究，总结规则 探究一：主谓一致 例句：（1）To change bad habits is never easy. （1） To help others gives a person satisfaction. （2） To prevent harmful habits like these from dominating a teenager’s life is essential. Tip 1: 动词不定式作主语时，谓语动词常用______________________。 探究二：it作形式主语的常用句式 例句：（1）It took the surgeon three hours to finish my mother’s lung surgery. （2）To join the people’s Liberation Army, it is required for men to shave off their beards. （3）It was not polite (of you) to disturb your neighbours with loud music last night. （4）It is important to avoid passive cigarette smoking. （5）It will take a nutrition specialist an hour to make a balanced diet menu for you. （6）As a chef, it was my duty to cook, so I tried to vary the meals in whatever way I could. （7）It can be easy for some teenagers to form bad habits. Tip 2: Sentence patterns with “it” and infinitives as the subjects ① It + is/ was + ______________ + ______________ sb + to do ② It is/was + ______________ + to do ③ It + takes/ took/ will take sb. + __________________ + to do ④ It + is/ was ______________ + for sb + to do 探究三：for/of的选择 例句：（1）It is smart __________ you to turn to a fitness consultant for advice. （2） It is dangerous ____________ you to take illegal drugs. Tip 3: 在 It + is/was + 形容词 + to do 的句式中, ① 当该形容词用以表示to do的特征时，使用 It is/was ＋ adj. ＋ ________ + sb. + to do； ② 当该形容词用来表示不定式的逻辑主语(sb.)的性质、特征或品德时，使用 It is/was ＋ adj. ＋ ________ + sb. + to do。 探究四：to do as the subject VS doing as the subject Use the correct forms of the words to fill in the blanks. 例句：（1）__________________ (read) aloud is good for your English learning. （2）It is quite necessary __________________ (read) it again. （3）__________________ (see) is to believe. （4）__________________ (see) is believing. Tip 4: 动词不定式和动名词作主语的区别： ____________作主语特指一次性的、具体的动作；____________作主语泛指一般的或习惯性的动作。 且作主语和表语的不定式或动名词需保持_____________。 探究五：疑问词 + 不定式 分析例句中疑问词 + 不定式作什么成分。 例句：（1）When to start has not been decided yet. ____________________ （2）Do you know where to find Tom? ____________________ （3）My main concern is how to get there on time. ____________________ Tip 5: 动词不定式可与疑问词when、where、how、what、which、who等组合，构成_______________________________，在句中可作______________、______________和______________。 3、 练习 1. 完成课本17页Activity 3 并回答How can we lose weight? 2. 完成课本17页Activity 2. 3. 在文中找到更多的to do结构并分析其成分。 4. 完成下列练习题。 （1） 填空 （1） ____________________ (learn) a new language requires patience and practice. （2） It is necessary __________ us __________ (keep) a balanced diet to stay healthy. （3） It takes my sister 40 minutes __________ (walk) to school every morning. （4） ____________________ (solve) this problem is the most important task for our team today. （5） It is very kind __________ you __________ (offer) me such useful advice. （6） ____________________ (read) widely without thinking is not a good way to study. （7） The question is __________ to start the project—we haven’t decided yet. (用疑问词填空) （8） It is a great pleasure __________ (invite) to speak at your school’s English festival. （9） ____________________ (master) a skill well takes years of consistent effort. （10） It is dangerous __________ children __________ (play) with fire near the forest. （11） I don’t know __________ to choose between these two books. (用疑问词填空) （12） ____________________ (finish) all the homework in one hour is impossible for me today. （13） It is important __________ us __________ (develop) good learning habits as early as possible. （14） ____________________ (visit) the Great Wall has always been my biggest dream. （15） It took the workers three months __________ (build) the new library in our town. （2） 句型转换 （1） To learn a foreign language well is not easy.（用 it 作形式主语改写句子）、 （2） It is helpful for us to read more books.（改为同义句，用不定式作主语） （3） To finish the work in two days is a big challenge for him.（用 it 作形式主语改写句子） （4） We don’t know what we should do next.（改为 “疑问词 + 不定式” 结构） （5） It took her three hours to clean the house last Sunday.（改为同义句，用不定式作主语） 1 / 7 学科网（北京）股份有限公司 学科网（北京）股份有限公司 $