人教版（2019）选择性必修 第三册Unit 2 Healthy Lifestyle Discovering Useful Structures课件（共16张）

(共16张PPT)
新人教选择性必修Book 3
Unit 2 Healthy Lifestyle
Discover useful structures P17
Underline the sentences in the text.
However, during this period, it can be easy for some of them to form bad habits.
To prevent harmful habits like these from dominating a teenager's life is essential.
They must learn to recognise bad habits early and make appropriate changes.
To change bad habits is never easy, even with many attempts.
We make a choice to do something, and then we repeat it over and over again.
Lead-in
Soon that choice becomes automatic and forms a habit that is much harder to change.
Firstly, there is a “cue”, an action, event, or situation that acts as a signal to do something.
The reward makes us much more likely to continue the 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, we could try to replace a negative routine with something more positive.
Aside from changing bad habits, we can also use the
habit cycle to create good habits.
You have the power to build a happy and healthy life
of good habits.
Lead-in
For example, when we come to an escalator, our normal routine is to ride it, but we could change this routine into something more positive by taking the stairs instead.
Many of us try to change bad habits quickly, and if we are not successful straight away, we often become pessimistic and give up.
In fact, the most successful way to change is not suddenly, but over a period of time.
To reach the goal of change, a person must show some discipline and repeatedly take many small steps.
After all, it is not easy to break bad habits.
For young people, there is plenty of time to change bad
habits.
Find more in the rest of the text.
Lead-in
Presentation/Practice
My mum keeps telling me to go out with my school friends instead.
It's important to meet friends in person from time to time, not just on social media.
When I set out to do something, I do my best to achieve it.
My target is to prepare myself for my degree in biology at university.
Li Ying is the first person to join the volunteering club in her class.
complement 宾语补足语
subject 主语
adverbial 状语
predicative 表语
attribute 定语
List the functions of the infinitives in the sentences.
动词不定式
动词不定式作主语
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。
To see is to believe.
It is right to give up smoking.
It's very nice of you to be so considerate.
1. 不定式具有名词的特征，可在句子中充当主
语。
To know oneself is difficult.
人贵有自知之明。
动词不定式作主语
不定式和动名词作主语的区别
不定式：表示具体的某次动作，特别是将来的动作。
To teach you the uses of the infinitive is my
job today.
教你们不定式的用法是我今天的工作。
动词-ing形式：表示比较抽象的、经常性的、一般性动作。
Teaching is my job.
教学是我的工作。
动词不定式作主语
2. 不定式和when/where/how/what/whether等连
用，在句子中作主语。
Whether to do it hasn't been decided.
是否去做还没有决定。
It is+ 形容词+for sb. +to do sth.常用于表示事物的特征特点，表示客观形式的形容词，如easy, hard, difficult, interesting, impossible等。
It's very hard for him to study two languages.
对他来说学两门语言是很难的。
3. it作形式主语句型：
动词不定式作主语
It is+ 形容词+of sb. +to do sth.的句型一般用表示人物的性格、品质，表示主观感情或态度的形容词，如good, kind, nice, clever, foolish, right等。
It's very nice of you to help me.
你来帮助我，真是太好了。
It is+ a/an +名词+to do sth.这样的名词有：a pity, a shame, a pleasure, one's duty, an honor等。
It's a great honor to be invited to your birthday party.
很荣幸被邀请参加你的生日聚会。
动词不定式作主语
It takes/costs/requires/makes sb./sth. to do sth.
It took me two hours to finish the work.
我完成那项工作用了两小时。
注意：
在It is +no use/ no good/ useless/fun/enjoyable/
tiring/ interesting/ foolish/nice/a waste of time/ a
pleasure...句型中常用动名词形式做真正的主语。
It's no use waiting here doing nothing.
无所事事地等待是没有用的。
（1）Sometimes it’s better 　　　___(remain)
silent.
（2）Although 　 is a hard task to protect our
environment, we can’t help but go ahead.
（3） 　　　 ______ (control) the air
pollution is necessary.
（4）It was foolish 　　him to endanger his life
in that way.
（5）Don’t you think it is rude 　 him to ask a
lady her age
Practice
语法填空：根据提示完成句子。
of
of
it
To control/Controlling
to remain
（6）It is difficult 　 　 him to live on such a
small salary.
（7）I don’t think _________________________
（你问……是不礼貌的） how long the
interview will last.
（8） 　　　　　　　_____　（保卫…… 是我
们的职责） the country against its enemies.
（9） 　　　　　　___　　 （ …… 花了我半
个小时）to wash the clothes.
Practice
语法填空：根据提示完成句子。
for
it is impolite of you to ask
It’s our duty to defend
It took me half an hour
Production
Join the words to make full sentences using the infinitive.
1. important/avoid/passive cigarette smoking.
_____________________________________________
2. will take/nutrition specialist/a balanced diet menu/make
/an hour/for you.
_____________________________________________
_____________________________________________
3. useful/turn to/fitness consultant/for advice
_____________________________________________
4. illegal /dangerous/take /drugs
_____________________________________________
5.harmful/skip breakfast/often
_________________________________________
2
It is important to avoid passive cigarette smoking.
It will take an hour for a nutrition specialist to make a
balanced diet menu for you.
It is useful to turn to a fitness consulant for advice.
It is dangerous to take illegal drugs.
It is harmful to skip breakfast (too) often.
Complete the conversations with the correct
forms of the phrases in the box.
3
1. A: Hello, doctor. I want to lose weight, but I just
can't seem to do it. What can you do to help
me
B: Well, first, it's necessary to ______________
what you eat. Cut out all fatty food and
sugary drinks, and eat more fruit and
vegetables.
2. A: I really need to _________a way to exercise
more.
I could use a fitness app, but my phone's full.
B: So delete a few files. I'm sure the app doesn't
take up much space.
begin with be in control of make a choice decide on make up one’s mind
be in control of
decide on
Complete the conversations with the correct
forms of the phrases in the box.
3
3. A: Before exercising, always do a few warm-ups
to__________.
B: I know. But then I always feel too tired to
continue!
4. A: Should I go for the pizza or the fried chicken
I hate ______________ like these. You know
what —I'm going to eat both!
B: Wow! Don't eat too much junk food-you'll get
fat. I've actually ________________ to go on
a diet, so I'll just stick to the fruit salad.
begin with be in control of make a choice decide on make up one’s mind
made up my mind
begin with
to make choices
Thank you!