UNIT 2 Section 3 Grammar(教用Word)-【赢在微点·轻松课堂】2024-2025学年高中英语选择性必修第三册（人教版2019）

Section 3　Grammar—不定式作主语 课前观察自主领悟 语法图解 观察句子 ① It takes three generations to make a gentleman. ②What a relief it is for us to succeed in our experiment at last! ③It was careless of you to leave your umbrella on the train. ④To do this is to cut the foot to fit the shoe. ⑤To read without reflecting is like eating without digesting. 我的领悟 1.所有黑体部分都是不定式作主语。 2.句①②③中黑体部分为句子的真正主语,句中的it为形式主语。 语法课堂高效学习 一、动词不定式作主语的概念 不定式作主语,表示具体的、一次性的或将来的动作;在很多情况下,人们通常用it作为形式上的主语,而把不定式移到谓语之后,使句子结构显得平稳一些。 ①To know something about English is one thing; to know English is quite another. 懂一点英语是一回事;完全掌握英语是另一回事。 ②It is impossible to learn a foreign language without making painstaking efforts. 想不下苦功就能学会一门外语是不可能的。 [提示]v.⁃ing作主语多表示一般性的、抽象的、重复性的动作或状态。 Reading poems gives me much pleasure. 读诗给我带来很多乐趣。 【小练1】　单句语法填空 ①To teach (teach) you the uses of the infinitive is my job today.  ②To look (look) after the safety of the community is his responsibility.  ③To solve (solve) this annoying problem is really out of the question.  二、动词不定式作主语的用法 1.不定式作主语通常位于句首,谓语动词常用第三人称单数形式。 ①To see is to believe.眼见为实。 ②To climb up the mountain road is easy while to go down the hills is hard. 上山容易下山难。 ③It is not easy to find your way to the town. 要找到去这个小镇的路很不容易。 2.用it作形式主语,把作真正主语的不定式(短语)后置,常用于以下句式中: (1)It+be+名词+to do sth ①It􀆳s our duty to take good care of the old. 照顾好老人是我们的责任。 ②It must be great fun to fly to the moon in a spaceship. 乘宇宙飞船飞往月球一定很有趣。 (2)It takes sb+some time+to do sth ①How long did it take you to finish the work? 你花了多长时间来完成这项工作? ②It took me more than an hour to do my homework yesterday evening. 昨天晚上我做作业用了一个多小时。 (3)It+be+形容词+for sb +to do sth ①It is difficult for us to finish writing the composition in a quarter of an hour. 在十五分钟内完成这个作文对我们来说太难了。 ②It is interesting for us to play with snow in winter. 冬季里玩雪对我们来说是很有趣的。 (4)It+be+形容词+of sb+to do sth ①It is stupid of you to write down everything the teacher says. 你将老师所说的话全部记下来是很笨的一种方法。 ②It􀆳s very kind of you to say so. 你这样说真是太好了。(可以说:You are very kind.) [提示]在“It is/was+adj.+for/of sb to do sth”结构中,若形容词侧重于评价人物的特性、特征,应用of,此时形容词常为kind,nice,foolish等,且sb与形容词之间可构成逻辑上的系表关系;若形容词侧重于描写不定式动作的特征、特点,应用for。 【小练2】　单句语法填空 ①It took years of work to reduce (reduce) the industrial pollution and clean the water.  ②Walking (walk) is a good form of exercise for both the young and the old. ③It is difficult for him to admit his mistakes. ④It was selfish of him not to share his dictionary with others. ⑤To finish (finish) the task will take a long time.  3.“疑问词+动词不定式(短语)”结构 动词不定式(短语)可与疑问词when, where, how, what, which, who等组合,在句中作主语。 ①Where to hold the meeting is still unknown. 会议地点还未知。 ②How to solve the problem has not been decided yet. 如何解决这个问题还未决定。 【小练3】　单句语法填空 ①How to cure (cure) this kind of illness is still unknown.  ②Whether to do it or not has not been decided. ③How to deal (deal) with such a person isn􀆳t known yet.  语法微练 Ⅰ.单句语法填空 1.It is wise to take (take) such gifts with gratitude.  2.He will find it is easy to make (make) friends in this city.  3.To get (get) there by bike will take us half an hour.  4.When to leave (leave) for London has not been decided yet.  5.It􀆳s necessary for you to lock the car when you do not use it. 6.To hold(hold) the meeting smoothly tomorrow is what I really expect.  7.It is terrible to see the ship sinking into the sea. 8.It was silly of you to give up such a good chance! Ⅱ.用不定式完成句子 1.步行去银行大约用十分钟。 It takes about ten minutes to walk to the bank.  2.对你们来说学好外语非常重要。 It􀆳s important for you to learn a foreign language well.  3.什么时候开会还没有定下来呢。 When to hold the meeting hasn􀆳t been decided yet.  4.想起那天发生的事情,我很震惊。 It shocked me to think of what happened that day.  5.母亲担心她的孩子这是很自然的。 It is natural for a mother to worry about  her own children. 学科网（北京）股份有限公司 $$