Unit 2 Healthy Lifestyle Discover useful structure 课件（28张）人教版（2019）选择性必修 第三册

(共28张PPT)
Lesson 3 Discovering Useful Structures
Infinitives as the Subjects
HEALTHY LIFESTYLE
Learning objectives
After this lesson, you will be able to:
1. understand the forms and functions of infinitives as the subjects;
2. use the infinitives flexibly and authentically in the real situations;
3. further discuss how to form a healthy lifestyle using infinitives of all types.
图片来自教材
图片来自教材
图片来自教材
To change bad habits is never easy.
Look at the following sentences and pay attention to the italicized infinitives.
subject 主语
subject 主语
subject 主语
subject 主语
It
is never easy
to change bad habits.
Tip 1：将形式主语 ______ 置于句首，____________ 置于句末，可以
避免句子头重脚轻、结构失衡。
it
动词不定式
Change the sentence structures.
Change the sentence structures.
To finish my mother’s surgery took the surgeon three hours.
To shave off their beards is required (for men).
To disturb your neighbours with loud music last night was not polite.
It is never easy to change bad habits.
Page 14~15
1
2
3
4
5
6
Task 1: Find more infinitives as the subjects.
1. However, during this period, it can be easy for some of them to form bad habits.
2. To prevent harmful habits like these from dominating a teenager's life is essential.
3. To change bad habits is never easy, even with many attempts.
4. After all, it is not easy to break bad habits.
It is essential to prevent harmful habits like these from dominating a teenager’s life.
It is never easy to change bad habits, even with many attempts.
However, during this period, to form bad habits can be easy for some of them.
After all, to break bad habits is not easy.
Change the sentence structures.
Translate the sentences from English to Chinese and then from Chinese to English.
1. However, during this period, it can be easy for some of them to form bad habits.
但是，在此期间，他们中的一些人很容易养成不良习惯。
2. To prevent harmful habits like these from dominating a teenager's life is essential.
防止像这样的有害习惯主宰青少年的生活是至关重要的。
3. To change bad habits is never easy, even with many attempts.
改变坏习惯绝非易事，即使尝试了很多次。
4. After all, it is not easy to break bad habits.
毕竟，要改掉坏习惯并不容易。
Tip 2: 动词不定式作主语时，谓语动词常用__________。
To change bad habits is never easy.
To help others gives a person satisfaction.
To prevent harmful habits like these from dominating a teenager’s life is essential.
Task 2: Observe and explore.
单数
图片来自网络
It will take a nutrition specialist an hour to make a balanced diet menu for you.
It is useful to turn to a fitness consultant for advice.
It is dangerous to take illegal drugs.
It is harmful to skip breakfast too often.
【Practice】 Use infinitives as the subjects.
To get healthy and get rid of bad habits, sometimes it is also a good idea to get professional help. It will take a nutrition specialist an hour to make a balanced diet menu for you. It is also useful to turn to a fitness consultant for advice. You can also help yourself with some common sense. For example, it is harmful to skip breakfast too often. It is important to avoid passive cigarette smoking. And, of course, it is dangerous to take illegal drugs too.
Suggested answers：
Task 3: Summarize the sentence patterns with “it” and with infinitives as the subjects.
It took the surgeon three hours to finish my mother’s lung surgery.
To join the people’s Liberation Army, it is required for men to shave off their beards.
It was not polite (of you) to disturb your neighbours with loud music last night.
It is important to avoid passive cigarette smoking.
It will take a nutrition specialist an hour to make a balanced diet menu for you.
As a chef, it was my duty to cook, so I tried to vary the meals in whatever way I could. (Textbook, Page 104)
It can be easy for some teenagers to form bad habits. (Textbook, Page 104)
Tip 3: 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
Tip 3:
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
adj.
for / of
n.
some time
V-ed
【Practice】Use the correct words to fill in the blanks.
It is smart ____ you to turn to a fitness consultant for advice.
It is dangerous ____ you to take illegal drugs.
of
for
Tip 4: 在 It + is/was + 形容词 + to do 的句式中, 当该形容词用以表示to do的特征时，使用 It is/was ＋ adj. ＋ ____ + sb. + to do；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。
for
of
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______。
不定式短语
When to start has not been decided yet.
Do you know where to find Tom
My main concern is how to get there on time.
subject 主语
object 宾语
predicative 表语
主语
宾语
表语
Task 4: Observe and explore.
【Practice】Use the correct forms of the words to fill in the blanks.
When ________ (start) has not been decided yet.
How ________ (use) the computer is the question.
It has been decided where ________ (spend) our winter holiday.
to start
to use
to spend
Use the correct forms of the words to fill in the blanks.
________ (read) aloud is good for your English learning.
It is quite necessary ________ (read) it again.
________ (see) is to believe.
________ (see) is believing.
拓展: to do as the subject VS doing as the subject
Reading
to read
To see
Seeing
Tip 6: 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________。
to do
doing
一致
图片来自网络
Healthy lifestyle contributes to our fitness.
图片来自网络
图片来自网络
But many people have the problem of overweight.
图片来自网络
be in control of
decide on
begin with
making choices
made up my mind
How can we lose weight
Eat healthily
Do exercise regularly
Drink enough water
Sleep enough
Stick to a healthy lifestyle
图片来自网络
Task 5: Find more sentences with infinitives.
Page 14~15
They must learn to recognise bad habits early and make appropriate changes.
We make a choice to do something, and then we repeat it over and over again.
The reward makes us much more likely to continue the habit cycle.
To facilitate a positive change in our bad habits, we must first examine our bad habit cycles and then try to adapt them.
For example, when we come to an escalator (cue), our normal routine is to ride it.
To reach the goal of change, a person must show some discipline and repeatedly take many small steps.
object 宾语
attribute 定语
complement 补足语
adverbial 状语
object 宾语
predicative 表语
adverbial 状语
Tip 7:
动词不定式可以在句中作______、______、______、______、______、________的成分。
主语
宾语
表语
定语
状语
补足语
In this lesson, we have learnt
1. the forms and functions of the infinitives used as subjects;
2. how to use infinitives in real situations;
3. what the infinitives function as in sentences.
Summary
1. Finish the exercise on Workbook Page 69.
2. Use infinitives to talk about healthy lifestyle.
3. Review what you have learned about
the infinitives.
Homework