Infinitive of purpose là gì

Use the words in brackets to answer the questions.

E.g. What do you listen to classical music for? [feel relaxed]

-> To feel relaxed, I listen to classical music. /I listen to classical music to feel relaxed.

We can use to + infinitive to say why we do something. It tells the other person the reason. We need to have a normal verb as well.

• I went on holiday [this is what I did] to relax [this is why I did it].
• She studies hard to get good marks.
• He gave up cakes to lose weight.
• I'm calling you to ask for your help.

Be careful! In many languages, we use 'for + infinitive'. This is not correct in English. NOT: I went on holiday for relax.

The main verb can be in any tense. For example:

• Present simple: I exercise every day to stay healthy.
• Present continuous: He's saving money to buy a flat.
• Past simple: I went to university to get a degree.
• Past continuous: She was walking to the shops to buy milk when she met John.
• Future simple: He'll come to the party later to pick up Julia.
• Present perfect: She's gone to the library to study.

We can also use 'in order to + infinitive' and 'so as to + infinitive'. 'In order to' is a bit more formal but the meaning is the same as 'so as to' and 'to + infinitive'.

• I went on holiday to relax.
• I went on holiday in order to relax.
• I went on holiday so as to relax.

We can use a negative infinitive of purpose by adding 'not' before 'to'. Often we do this with 'in order not to' and 'so as not to'.

• I drank coffee in order not to fall asleep.
• He got up very quietly so as not to wake the children.

We can only use the infinitive of purpose if the subject of the main verb and the infinitive of purpose are the same. If they are different, we use 'so that + clause' or 'in order that + clause'.

• I went to the library to study. [I went to the library and I studied - the subject are both 'I'.]

BUT

• I went to the library so that John could study. [I went to the library, but John studied. The two subjects are different - I and John - so we can't use an infinitive of purpose.]

With the verbs 'come' and 'go', we use an infinitive of purpose when they're in a normal tense but we often use 'and + infinitive' with imperatives or after modal verbs.

• I went home to sleep.
• Go home and sleep!
• You must go home and sleep!

Try an exercise about this here.

1. Một mệnh đề nguyên thể có to có thể diễn đạt một mục đích.
Laura has gone to town to do some shopping. [Laura đến thị trấn để đi mua sắm.]
I'm writing to enquire about activity holidays. [Tôi viết thư này để biết thêm về các hoạt động nghỉ lễ.]
To get a good seat, you need to arrive early. [Để có chỗ ngồi tốt, bạn cần đến sớm.]
Chú ý:
a. Trong tiếng Anh-Anh thông thường, ta thường dùng go and/come and hơn là go to/come to.
I'll go and fetch a hammer. [Tôi sẽ đi và lấy búa.]
Come and have a look at this. [Lại đây và nhìn cái này đi.]
Người Mỹ thường nói: I'll go fetch a hammer.
b. Sau going và coming ta dùng nguyên thể có to.
Mark is coiming to look at the photos. [Mark đang tiến đến xem ảnh.]

2. Ta đôi khi có thể dùng mệnh đề nguyên thể có to để diễn tả kết quả, dù cho cách sử dụng này hơi mang tính văn chương.
Laura came home to find her house on fire. [Laura về nhà và thấy nhà mình bị cháy.]
He grew up to be a handsome young man. [Cậu bé lớn lên và trở thành một chàng trai trẻ đẹp trai.]

Nguyên thể có to có thể diễn đạt ý " tin xấu" theo sau "tin tốt". Ta thường dùng only trước nguyên thể.
I found my keys only to lose them again. [Tôi tìm được chìa khóa để rồi lại làm mất chúng.]
Charles arrived for the concert [only] to find it had been cancelled. [Charles đến buổi hòa nhạc để rồi thấy nó đã bị hủy.]

3, Mệnh đề nguyên thể cũng có thể diễn đạt một bình luận trong câu.
To be frank, you didn't make a very good impression. [Nói thật, cô đã không tạo ấn tượng tốt.]
I'm a bit tired of sightseeing, to tell you the truth. [Tôi đã quá mệt mỏi với những chuyến tham quan, nói cho anh biết sự thật.]

Bài 1: Use a sentence from A and a sentence from B to make a new sentence, using to-infinitive of purpose:

A                      

1. I shouted.              

2. I had to go to the bank.               

3. I’m saving money.          

4. I went to the hospital.      

5. I’m wearing two sweaters.      

6. I called the police.            

B

a. I want to keep warm.

b. I wanted to report that my car had been stolen.

c. I want to go to Canada.

d. I had to have an operation.

e.  I had to have an operation.

f. I wanted to warn people of the dange.

⇒1. I shouted to warn people of the danger.

2. I had to go to the bank _____________________________________________________.

3.  ______________________________________________________________________.

4. _______________________________________________________________________

5. _______________________________________________________________________

6. _______________________________________________________________________

Bài 2: Combine each pair of sentences, using clauses of purpose:

1. I hurried. I didn’t want to be late.

→ I hurried so that I wouldn’t be late.

2. We wore warm clothes. We didn’t want to get cold.

→ We wore _____________________.

3. The man spoke very slowly. He wanted me to understand what he said.

→ The man _________________________________________________________________.

4. Please arrive early. We want to be able to start the meeting on time.

→ Please ___________________________________________________________________.

5. She locked the door. She didn’t want to be disturbed.

→ _________________________________________________________________________

6. I slowed down. I wanted my car behind me to be able to pass.

→ _________________________________________________________________________

Bài 3: Choose the word or phrase that best completes each sentence:

1. People in the world must unite their efforts ___________ maintain and protect peace.

A. so that              

B. in order to                  

C. for                

D. so as

2. Some young people like to earn their own living ____ they will be independent from their parents.

A. if                    

B. in order                    

C. in case                

D. in order that

3. We went to a restaurant _______ celebrate my birthday.

A. so as not            

B. so that                    

C. so as to              

D. in the event that

4. ____ for the company to be profitable, sales would need to rise by at least 60 %.

 A. In order              

B. So                        

C. In order                  

D. In order that

5. “He left a message so that I could know where to find him.” Means _____________.

A. He left a the message, which I knew where to find.

B. He left a message, because I knew where to find him.

C. I could know where to find him thanks to the message he left.

D. I could know where to find him, so he left a message.

Bài 4: Choose the part in each sentence that needs correction:

1. I always keep fruit in the fridge in order for me to keep insects off it.

A. keep fruit 

B. for me 

C. to keep 

D. off it

2. To turn on the light, I was surprised at what I saw.

A. To turn on 

B. was

C. at

D. what

3. In addition to save on gas, the modern car is designed to save on maintenance expenses.

A. save on 

B. the

C. is designed 

D. save on maintenance                     

4. In purchasing a winter coat, it is very important for trying it on with heavy clothing underneath.

Infinitive nghĩa là gì?

Bare inf trong tiếng Anh là gì?

Bare infinitive viết tắt là gì?

Present infinitive là gì?