THE INFINITIVE
Nguyen Kim Anh-DFL
1. Form
2. Uses
A. Full infinitive
B. Bare infinitive
I. FORM
1. Full infinitive vs. Bare infinitive
- Full infinitive: to + verb ( to love, to die, etc)
- Bare infinitive: verb without “to” (love, die, etc)










- Present infinitive: to work, to die
- Present continuous infinitive: to be working
- Perfect infinitive: to have worked

2. Infinitive forms

- Perfect continuous infinitive: to have been working
- Present infinitive passive: to be done
- Perfect infinitive passive: to have been done
II. USES OF THE INFINITIVE
1. The infinitive may be used alone
E.g. She pretended to cry.

or as part of an infinitive phrase
E.g. She began to walk down the road.



2. The infinitive may be the subject of a sentence
E.g. To win her heart is not easy at all.
To learn a language well takes a long time.
To be or not to be is a big question

3. The infinitive may be the complement of a verb
E.g.
My ambition is to learn English well.
What he wants is to win her heart.

4. The infinitive may be the object or part of the object of a verb:
Follow the verb directly:
E.g. He promised to keep it secret.
We managed to finish the task.
They wanted to be successful.
Follow verb + how/ what/ etc:
E.g. He doesn’t know what to do.
I am wondering how to go there.
Follow verb + object:
E.g.
He persuaded her to go out with him.
Parents want their children to be happy.

5. Be + infinitive can express commands or instructions
E.g.
No one is to leave this building without permission of the police.
He is to stay here till we return
6. The infinitive can express purpose
E.g.
He went abroad to study English.
I just call to say I love you.


7. The infinitive can be used after certain adjectives
E.g.
I am sorry to hear that she has said goodbye to you.
We are happy to see you hear.
8. The infinitive can connect two clauses
E.g. I asked her a question to make sure that she still loved me.
9. The infinitive can sometimes replace relative clauses
E.g.
You are the very last person to know about that.
She is the only student to pass the exam.
10. The infinitive can be used after certain nouns
E.g.
It was a great pleasure to meet you.

11. The infinitive can be used with too/ enough and certain adjectives/ adverbs
E.g. You are too young to understand about love.
She is not mature enough to live alone.

12. An infinitive phrase such as to tell the truth, to be honest, can be placed at the beginning or end of a sentence.
E.g. To be honest, I don’t like him.
To tell the truth, your plan doesn’t sound persuasive.
A. Full infinitive
1. As a subject
2. After certain verbs
3. Phrases followed by the infinitive
4. After verbs followed by a question word
5. After the object of certain verbs
6. After certain adjectives
7. After would like, would love, would prefer
8. After the first/ second/ next/ last/ best, etc instead of a relative clause
9. After certain nouns
10. After some, any, no and their compounds
11. After the following structures
12. With too/ enough

The infinitive as the subject
a. Infinitive/ Infinitive phrase + appear/seem/be
E.g. To save money now seems impossible.
To listen carefully appears necessary.
To work hard is very important.

b. More usually, pronoun IT can be put first, and infinitive/ infinitive phase is moved to the end.
E.g.
It seems impossible to save money now.

c. It +be + adjective + infinitive
E.g. It is wonderful to love and to be loved.
(Sometimes a noun can be used instead of an adjective)
E.g. It is a mistake to follow him.
d. Cost/take + object +infinitive
E.g. It takes years to learn a language well.
e. S + believe/ consider/ discover/ expect/ find/ think/ (that)/ wonder (if) + it is adjective+ infinitive
E.g. We think it is safe to go by train.
They believe it is good not to smoke.
f. FIND: we can omit THAT + verb BE
E.g. He found that it was easy to earn money.
= He found it easy to earn money.
g. Perfect infinitive can be used as the subject of a sentence
E.g. To have made the same mistake twice was unforgivable.
Or we can put IT first
E.g. It is better to have loved and lost than never to have loved at all.
2. After certain verbs (as their object)
1. She agreed to accept his marriage proposal.
2. They managed to break into my house.
3. The young man refused to stay at home.
4. She volunteered to help me.
5. She pretended not to have seen him.
6. Unemployment levels tend to rise in Europe.

3. Phrases followed by infinitive
Be about ( He is about to leave)
Be able/ afford
Do one’s best/ do what one can
Make an/ every effort
Make up one’s mind
Occur + to + object
Set out
Take the trouble
Turn out
4. After verbs followed by a question word (who, what, which, where, how, but not why)
ask, decide, explain, forget, know, learn, remember, show, tell, understand, wonder, etc.
Have you decided when to get married?
Do you remember what to buy?
Could you show me how to win your heart?
5. After the object of certain verbs
My friend invited me to join them.
They persuaded her to see him again.
I begged him to love me.
The teacher told us to raise questions.

Help + object can take either a full or bare infinitive
E.g. Could you help me ( to) pack my suitcase?

6. After certain adjectives
Jack was relieved to hear his son was out of danger.
You have to be careful not to say anything insulting.
He is lucky to have such a wife.
I am glad to hear that.
7. After would like, would love, would prefer
I would prefer to be on holiday instead of working.
Would you like to go to the cinema with me?
8. After the first/ second/ next/ last/ best, etc instead of a relative clause
If anything happens, you`ll be the first
to know.
Joan was the last to hear about the accident.
9. After certain nouns
It is my pleasure to help you.
It was a great shock to hear about the accident
He made an attempt/effort to win the gold medal.
Their offer/plan/ promise to rebuild the town was not taken seriously.

10. After some, any, no and their compounds
I`ll make you something to eat.
He doesn`t have anywhere to stay.
She has nothing to do, nowhere to go and no one to love.

11. After the following structures
a. it + be + adjective + (of/ for + object)
It`s very comforting to listen to your voice.
It is nice to see you here.
b. generous, good, kind, nice, polite, stupid, etc + of object
E.g. It was very kind of her to call.
It was impolite of him to say so.
c. difficult, easy, essential, important, (un) necessary, (un) usual, etc + for object
It is necessary for him to have a rest.
It is very difficult for me to talk with him.
d. so +adjective + as, in formal or polite requests
E.g. Would you be so kind as to help me with these suitcases?

12. With too/ enough
a. too + adjective/ adverb = negative meaning
E.g. He was too drunk to drive home.
They worked too slowly to finish the work in time.
b. too + adjective + a + noun
E.g. He is too experienced a conductor to mind what the critics say.
c. enough + noun
E.g. He had enough patience to listen to her.
He doesn’t earn enough money to live on.
There isn’t enough time to discuss this issue.

d. adjective/ adverb + enough
She is tall enough to become a model.
He spoke slowly enough for everyone to understand.
They are intelligent enough to understand what you mean.
e. so + adjective + as
He was so foolish as to leave his car unlocked.
You are so kind as to help me with my homework.



13. At the beginning of the sentence in fixed expressions (to be honest, to tell you the truth, to begin with, etc)
To be honest, I didn`t want to meet him again.
To begin with, I will talk about full infinitive.
To cut a long story short, we said “NO”
B. Bare infinitive
1. After most modal verbs
2. After would rather, would sooner, had better
3. After some certain verbs
4. In the following structures
1. After most modal verbs ( can/ could, may/ might, will/ would, shall/ should, must, etc )
You should wake up earlier in the morning.
We must go to school on time.
Can you show me the way to your heart?
Will you marry me?
2. After would rather, would sooner, had better

We’d rather stay at home.
You`d better attend the class regularly.
I would rather die than tell a lie.
unreal past is used.
I`d rather you didn`t make so much noise.
3. After some certain verbs
hear let make notice
observe see watch etc
Will you let me be alone?
She heard him come in.
The sad movie made me cry (lyric)
These verbs (except for let) take the full infinitive in the passive voice.
He usually makes his sister cry but yesterday he was made to cry by her.
He was seen to open the door.
We were made to do some extra work.
4. In the following structures
a. Why..?/ Why not...? (suggestions/advice)
Why not have another drink?
Why walk when I could give you a lift?
Why cry when there are a lot of fish in the sea?
b. do + anything/ everything/ nothing + but/ except + infinitive
My son does nothing all day but watch TV.
He did everything for her except marry her.
We will do anything you want except tell a lie.