Unit 2 Healthy Lifestyle Discover useful structures 学案-2022-2023学年高中英语人教版（2019）选择性必修第三册

设计人: 冯钰 审核人： 靳春福 时间：2023年 2月 6 日 编号： Unit 2 Healthy lifestyle——Discover useful structures The Infinitive as the Subject 【课标要求】 该部分为语法部分，内容是动词不定式（infinitives）作主语，活动围绕本单元的主题“健康的生活方式”展开。该部分的三个练习体现了从感知语法现象，发现语法形式表达的意义和功能，到完成控制性的书面操练，再到真实语境中正确选用目标语言结构的语法学习过程。 【学习目标】 1. Know the different forms of the infinitive; 2. Master the use of the infinitive as the subject; 3. Use the infinitive as the subject in the specific context correctly. 【学习重难点】 1. How to summarize the forms and functions of the infinitive. 2. How to use the infinitive as the subject in the specific context correctly. 【课前预习案】 预习课本P17并完成相应习题。 【合作探究案】 ★ Lead in Task 1 Read the following sentences and analyze what part does the underlined part serve as in each sentence? 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 neighbors with loud music last night. Task 2 Compare the following sentences and find the differences of the subjects. 1. To change bad habits is never easy, even with many attempts. 2. To prevent harmful habits like these from dominating a teenager’s life is essential. 3. After all, it is not easy to break bad habits. 4. However, during this period, it can be easy for some of them to form bad habits. 5. How to use the computer is a question. 6. When to go there has not been decided yet. · Summary 动词不定式作主语有三种形式： 1.直接放在 ________ 作主语； 2.为了保持句子平衡，用________作形式主语，放在句首，把真正的主语—动词不定式置于句后； 3.和 _________ 构成短语作主语。 ★Observe and discover Observation 1 1. To see is to believe. 2. To do this is to cut the foot to fit the shoe. 3. To say is one thing and to do is another. 4. To make a detailed plan is a good idea to make it successful. · Discovery 1 从位置上看，动词不定式作主语，通常放在句首。当句子主语和表语都是非谓语时，通常要_________，例如： To see is to believe. = Seeing is believing. Observation 2 1. For him to admit hi