北师大版 (2019)必修 第一册Lesson 3 Your Life Is What You Make It教课ppt课件

Grammar ——动词不定式

探究发现

①It's important to meet friends in person from time to time, not just on social media.

②It's so convenient to be able to compare the quality and prices from different online shops before I buy.

③I tend to set a goal for every subject at the beginning of each term.

④My target is to prepare myself for my degree in biology at university.

⑤My aim is to do well in every subject this term.

⑥I often use the time to review English words.

⑦To achieve all I want, I must use my time well.

⑧Li Ying is the first person to join the volunteering club in her class.

⑨My mum keeps telling me to go out with my school friends instead.

[我的发现]

1．句①、②中动词不定式短语在句中作真正的主语；it作形式主语。

2．句③中动词不定式短语在句中作宾语。

3．句④、⑤中动词不定式短语在句中作表语。

4．句⑥、⑦中动词不定式短语在句中作状语。

5．句⑧中动词不定式短语在句中作定语。

6．句⑨中动词不定式短语在句中作宾语补足语。

一、语法图解

二、语法突破

动词不定式是一种非谓语动词形式，其结构为“to＋动词原形”，其中to是动词不定式的符号。动词不定式没有人称和数的变化，其否定形式是在to前加not。不定式具有动词的特征，与其后面的名词等构成不定式短语；不定式具有名词、形容词和副词的作用，可以在句中作主语、表语、宾语、宾语补足语、定语、状语。

(一)动词不定式的三种主要结构模式

1．带to或不带to：(to) do sth

Our teacher asks us to be grateful to our parents.

老师告诉我们要感恩父母。

I saw a stranger enter our community.

我看见一个陌生人进了我们社区。

He told me not to move until he finished the drawing.

他告诉我等到他画完了画我再动。

2．疑问词＋不定式：how/when/what＋to do sth

这一结构在句中可作主语、宾语或表语等，常可转换成一个由该疑问词引导的从句。

He told us what to do.(＝He told us what we should do.)

他告诉我们该做些什么。

3．动词不定式的复合结构

动词不定式的复合结构为“for/of＋名词/代词(宾格)＋动词不定式”，常用于“It is/was＋形容词＋for/of＋sb＋不定式”这一句型中。当句中的形容词修饰动词不定式时，用介词for；修饰sb时，用介词of。

It is important for him to attend every day.

他每天都要出席，这很重要。

It is kind of you to help me with my English.

你帮我学英语真是太好了。

[即时演练1]　句型转换

①I don't know when we will hold the meeting.

→I don't know when to_hold the meeting.

②We made him work five hours a day.

→He was made to_work five hours a day.

③The box is so heavy that I can't carry it.

→The box is too heavy for me to_carry.

(二)动词不定式的时态和语态

动词不定式的时态和语态的形式见下表：

[即时演练2]　用所给动词的正确形式填空

①She seems to have_heard (hear) about this matter.

②He was said to have_been_told (tell) about the news.

③The weather seems to_be_improving (improve) now.Let's go for a picnic.

(三)动词不定式的用法

1．不定式作主语

(1)不定式作主语，表示特指的一次性的具体动作。

To say is one thing；to do is another.

说是一回事，做是另一回事。

(2)为了避免句子的头重脚轻，可以用“it”作形式主语，而把真正的主语——动词不定式(短语)放在句末。

It is not easy to learn English well.

学好英语不容易。

It is nice not to be dependent on them.

不依靠他们是好的。

[即时演练3]　句型转换

①To get up early is a good habit.

→It_is a good habit to_get_up_early.

②It is difficult to speak a foreign language well.

→To_speak_a_foreign_language_well_is difficult.

③It is necessary to remember enough words.

→To_remember_enough_words_is necessary.

2．不定式作表语

(1)不定式作表语一般表示具体的动作，特别是表示将来的动作。

My wish is to join the army after graduation.

我的愿望是毕业后参军。

(2)如果主语的中心词是aim, duty, hope, idea, job, plan, problem, wish等，或是以what引导的名词性从句，不定式作表语对其作补充说明。

His job is to feed animals.

他的工作是喂养动物。

[即时演练4]　补全句子

①My work is to_clean_the_room every day.

我的工作是每天打扫房间。

②His dream is to_be_a_doctor.

他的梦想是当一名医生。

③It seems to_be_an_interesting_book.

它看起来是本有趣的书。

3．不定式作宾语

(1)有些及物动词常用动词不定式作宾语。这些动词有：like，want，try，begin，decide，ask，forget，promise，hope，love, offer, refuse，wish等。

She longed to go back to her hometown.

她渴望返回家乡。

(2)动词不定式在介词but, other than后面时，如果介词前有行为动词do 的某种形式，那么介词后的不定式不带to，否则就要带to。

We could do nothing but/other than wait.

除了等待我们别无他法。

(3)作宾语的不定式如果带有自己的补足语，则须用it 作形式宾语，而将不定式短语(真正的宾语)放在宾语补足语之后。常用句型： 主语＋find/feel/think/believe/consider/make＋it＋adj./n.＋to do sth

I find it useful to learn English well.

我发现学好英语很有用。

[记忆口诀]

常见的只能用动词不定式作宾语的动词

决心，学会，想，希望(determine/decide，learn，want，hope/expect/wish)

拒绝，设法，愿，假装(refuse, manage, care, pretend)

主动，答应，选，计划(offer, promise, choose, plan)

同意，请求，帮一帮(agree, beg, help)

[即时演练5]　补全句子

①He agreed to_help_us.

他同意帮助我们。

②We finally decided to_stay where we were.

我们最终决定待在原地。

③We all hope to_see_the_great_musician.

我们都希望见到那位伟大的音乐家。

④I find it hard to_get_along_with_him.

我发现与他相处是件难事。

⑤We thought it_wrong_to_tell_her.

我们认为告诉她是错误的。

4．不定式作宾语补足语

(1)常跟不定式作宾语补足语的动词有advise，allow，ask，tell，teach，encourage，cause等。

The teacher encouraged us to write a composition every week.

老师鼓励我们每周写一篇作文。

(2)感官动词和使役动词后面作宾语补足语的不定式不带to，但变为被动语态时，作主语补足语的不定式需带to。常见的上述词有：一感：feel；二听：listen to，hear；三使：let，have，make；四看：see，watch，notice，observe等。另外，help后作宾语补足语的不定式符号to可有可无。

[图解助记]

I saw him go upstairs just now.

我刚才看见他上楼了。

He was seen to go upstairs just now.

有人看见他刚才上楼了。

[名师点津]　下列结构中用不定式作主语补足语，例如be said/reported/believed/ considered to等。

Our football team is reported to have won the match.

据报道，我们的足球队赢得了这场比赛。

[即时演练6]　补全句子

①My boss told me_to_type_out two letters.

我的老板让我打两封信。

②I didn't expect you_to_arrive here so soon.

我没有料到你会来得这么快。

③Please remind me_not_to_be_late_for the meeting.

请提醒我开会不要迟到。

④He asked me_to_talk_about English study.

他请我谈谈英语学习。

5．不定式作定语

(1)不定式作定语，与其被修饰的词在逻辑上有主谓关系或动宾关系。

He's always the first one to get up.(主谓关系)

他总是第一个起床。

Please give me something to drink.(动宾关系)

请给我点喝的。

[名师点津]　动词不定式作定语，且与被修饰的词有逻辑上的动宾关系时，不定式动词应该是及物动词；如果不定式动词为不及物动词，则该动词必须与介词连用，使其成为及物的动词短语。

Because the room was very crowded, I needed a tall bench to stand on.

因为房间里很拥挤，我需要一条高板凳站上去。

He wanted to find a new house to live in.

他想找一所新房子住。

(2)当名词或代词被序数词、形容词最高级the first，the last等修饰，且不定式与其逻辑主语为主谓关系时，常用动词不定式作定语。

He is the best man to do the job.

他是做这份工作的最佳人选。

(3)当被修饰词是表示抽象意义的名词时，常用不定式作后置定语，且不定式常用主动形式。常见的此类名词有ability, chance, idea, attempt, plan, way, opportunity等。

They failed in their attempt to reach there before five o'clock.

他们试图在五点钟以前到达那里，但失败了。

[即时演练7]　补全句子

①This is the key _to_open_the_front_door.

这是开前门的钥匙。

②Here is some paper for you to_write_on.

这是一些纸，你可以在上面写字。

③He was always the_first_to_come and the_last_to_leave.

他总是第一个来，最后一个走。

6．不定式作状语

不定式作状语主要有三种情况：

(1)目的状语。in order to和so as to是不定式作目的状语的正式用法，其中so as to不可置于句首。

In order to finish the work in time, we work late into the night every day.

为了能及时完成任务，我们每天工作到深夜。

(2)结果状语。通常有句型：too ...to do sth; ...enough to do sth; only to do sth。

I walked all the way from home to the library，only to find it closed.

我从家一直步行到图书馆，结果发现它关门了。

[名师点津]　不定式短语表示结果时，常与only连用，暗示一种意外的结果。

(3)原因状语。主要放在表示喜怒哀乐(glad, pleased，sad, worried, sorrow, excited等)的情感的词汇之后。

She seemed surprised to meet us.

遇见我们，她看起来有点惊讶。

[即时演练8]　补全句子

①She came to_see_me yesterday.

她昨天来看我了。

②She arrived early to_get_a_good_seat.

她到得很早，为的是得到一个好座位。

③I hurried to his house, only to_find him out.

我急急忙忙赶到他家，结果却发现他不在家。

维度一　基础题型练

单句语法填空

1．Sometimes I act as a listening ear for fellow students to_talk (talk) over what is bothering them.

2．To_learn (learn) more about Chinese culture，Jack has decided to take Chinese folk music as an elective course.

3．There were many talented actors out there just waiting to_be_discovered_(discover)．

4．If you are the last student to_leave (leave) the room，remember to turn off the lights.

5．With so many things to_deal (deal) with, I have to work late into the night.

6．I am sorry to_give (give) you so much trouble.And thank you for your help.

7．The doctor told the child to_eat (eat) less and sleep more.

8．They were made to_work (work) twenty hours every day.

9．I do not know what to do and where to go.

10．The best way to_improve (improve) your English is to_join (join) an English club.

维度二　语法与写作

补全句子

1．She got up early to_catch_the_early_bus.

她起得很早，为的就是赶上早班车。

2．I strongly advise you not_to_do_this.

我强烈建议你不要这样做。

3．I arrived at the shop only_to_find_I'd_left_all_my_money at home.

我到商店却发现钱全落在家里了。

4．He is not the kind of man to_do_such_things.

他不可能是做这种事的人。

5．It_is_convenient_for_us to be able to use computers.

能够使用电脑对我们来说很方便。

6．The purpose of education is to_develop_a_fine_personality in children.

教育的目的是培养儿童良好的品格。

维度三　语段练习

用动词不定式的适当形式填空

In Henan Province and Shandong Province, China, the senior high school life is extremely tough and boring.Parents count on their children 1.to_be_admitted (admit) into key universities.As a result, higher grades mean everything, and self­control is very important 2.to_succeed (succeed)．Some are begged 3.to_work (work) hard; some are forbidden 4.to_watch (watch) TV.

5．To_conclude (conclude), people here spare no efforts 6.to_defeat (defeat) others and 7.to_get (get) high marks comes first.