The infinitive is a non-finite form of the verb which has the following verb characteristics: tense, aspect and voice distinctions:
| Active | ||
| Simple | to do | to be done |
| Continuous | to be doing | - |
| Perfect | to have done | to have been done |
| Perfect Continuous | to have been doing | - |
To form the negative, we simply put not immediately before the infinitive:
She warned me not to be late. (To-infinitive)
She should not be told about it. (Bare infinitive)
The simple infinitive indicates that the action expressed by the infinitive is simultaneous with the action of the finite form of the verb in the sentence:
/ know him to be a very good student. He helped me to carry the box.
When associated with modal verbs and their equivalents, the simple infinitive may also refer to a future action:
It may rain tomorrow.
The continuous infinitive lays the emphasis on the duration of the action that is simultaneous with the action of the finite form of the verb in the sentence:
/ was pleased to be driving the car again.
The perfect infinitive shows that the action expressed by the infinitive precedes the action indicated by the finite form of the verb:
/ am glad to have taken your advice.
The perfect continuous infinitive denotes an action in progress which lasted for some time before the action (or state) expressed by the finite verb:
/ am pleased to have been doing this work all the time.
After the past tense of verbs expressing hope, expectation, intention the perfect infinitive is used to indicate that the action was not carried out:
I meant to have called you but I didn't have time.
He hoped to have come.
In common with the finite forms of the verb, the infinitive of a transitive verb has a direct object and is modified by an adverb:
I saw him drive a motorcar.
Her aim is to speak English fluently.
Uses of the Infinitive
1. The infinitive may be the subject of a sentence.
To save money now seems impossible.
To know how to drive is useful. Or It is useful to know how to drive. (It is more usual to place the pronoun it first.)
Note the use of introductory it in interrogatives:
Would it be safe to camp here?
2. The infinitive may be the complement of the verb.
His plan was to keep the affair secret.
3. The infinitive may be the object or part of the object of a verb. It can follow the verb directly:
He wants to pay now.
Or follow verb + question words:
Please show me what to do. = What should I do? Please show me. Can you tell me how to get there? = How do I get there? Can you tell me? Or follow verb + object.
She wants Peter to come on Monday.
NOTE: The infinitive as object or complement of the verb is used after the verbs:
want need
would like
would love
would prefer
would hate
hope
expect
plan
intend
mean
long
decide
choose
promise
propose
agree
refuse
seem
appear
pretend
attempt
help
claim etc.
4. The infinitive can be used after certain nouns and pronouns:
Many nouns that correspond to verbs can be followed by a to-infinitive:
I do not wish to see you. I have no wish to see you.
He refused to help me. His refusal to help me was a surprise.
We agreed to meet later. We made an agreement to meet later.
Other verb / noun pairs like this are:
to apply - an application to attempt - an attempt
to decide - a decision to propose - a proposal
to determine - determination,
to plan — a plan, etc.
5. The infinitive can be used after adjectives:
Adjective + to infinitive is used:
1) to express simple emotions and attitude:
to be anxious / determined / pleased / happy / easy / sure / (un) likely, etc. + to-infinitive
I’ т pleased to be here.
He is sure to do the work.
2) to praise / to criticise people:
to be right / wrong / silly / generous / selfish / stupid, etc. (of smb.) + to-infinitive
It was kind of you to ask them to come.
Wasn't it clever to do that!
3) after comparative or superlative of adjectives and expressions with adverbs too and enough:
It would be more interesting to go out.
The piano is too heavy to move.
He is not strong enough to move this box.
6. The infinitive can express purpose.
We use to do, in order to do and so as to do to express purpose. They answer the question "Why?" or "To do what?"
To get
I went to college in order to get a better job later.
So as to get
Note the negative forms:
I went to the city not to see the sights, but to find a job.
Phone for details of our holidays immediately in order not to miss this wonderful opportunity!
They exchanged addresses so as not to lose touch with each other.
7. The infinitive can be used with introductory or final set expressions.
To put it mildly, you are not very polite.
I've never met him, to tell you the truth.
To be honest, I liked it greatly. etc.
