Unit1 Period Ⅱ Grammar-【优化探究】2023-2024学年新教材高中英语选择性必修第三册同步导学案配套教参（人教版）

Period Ⅱ　Grammar 单元语法：Infinitives as the predicative (动词不定式作表语) 授课提示：对应学生用书第11页 [语法体会] 诵读下列例句并感知黑体部分的共性 (1)[教材原文]Perhaps the best way to understand Western art is to look at the development of Western painting over the centuries. (2)[教材原文]During the Middle Ages，the purpose of Western art was to teach people about Christianity. (3)[教材原文]In this work，Monet's aim was to convey the light and movement in the scene... (4)[教材原文]What they attempted to do was no longer show reality，but instead to ask the question，“What is art？” 1．所有黑体部分的动词不定式均作表语。 2．其主语常常是purpose，aim，way等表示意向、打算、计划的词及what 引导的主语从句等。 [知识精要] 动词不定式是非谓语动词的一种，它没有人称和单复数的变化。动词不定式具有名词、形容词和副词的特征，在句中可以作主语、宾语、表语、定语、状语、宾语补足语等，但不能作谓语。 一、基本用法 动词不定式可以放在be、become、sound、taste等系动词后面作表语。具体用法如下： 1．常见的动词不定式作表语，一般紧跟在系动词如be、seem、remain、appear、get等后面，用来说明主语的内容，也可表示将来的动作。 The next step is to make sure that you know exactly what is required.下一步是确保你明确知道需要什么。 The purpose of education is to develop a fine personality in children.教育的目的是发展儿童良好的品格。 Her wish is to become a key college student after graduation.她的愿望是毕业后成为一所重点大学的学生。 2．常用be to do来表示计划、安排、命令、注定、目的、应该、可能等意义。 That experience was to change his whole life.那次经历会改变他的一生。(注定) You must speak out，if we are to remain friends.如果我们要继续做朋友，你必须直言不讳。(目的) They are to marry next week.他们将在下周结婚。(安排) Children are not to smoke.儿童不准吸烟。(禁止) 3．不定式作表语，可用主动形式表示被动意义。 She is to blame.她应该受到责备。 A great deal is yet to do.还有许多事要做。 4．“疑问词＋不定式”结构作表语 疑问词who、what、which、when、where、how、why后加动词不定式构成不定式短语，它在句中可作主语、宾语和表语。 Our difficulty is where to find a guide leading us into the rainforest.我们的困难是在哪里可以找到一个带领我们进入热带雨林的向导。 The biggest challenge is how to prevent the spread of flu effectively. 最大的挑战是如何有效阻止流感的传播。 二、动词不定式和动名词作表语的区别 动词不定式和动名词都可以作表语。但用法有区别：表示一般的、泛指的或习惯性的行为用动名词；表示具体的、一次性的或将来的动作用不定式。 Mary's task is to set the table.玛丽的任务是去摆桌子。 His job is looking after sheep.他的任务是照看羊。 ▲但这种区别并不是绝对的。例外的情况也不少，比如在job、problem 等名词后面就可用不定式或动名词作表语，且意思区别很小。如： The problem is finding the time to get things done.问题是要找到完成这些事情的时间。 The problem