What is Infinitive?

An INFINITIVE is a verb form that connects to and the base form of the verb.

Generally, INFINITIVE are not affected by tenseOpens in new window, numberOpens in new window or personOpens in new window. They can be used as adjectivesOpens in new window or adjectival phrasesOpens in new window.

The INFINITIVE can also be used as an adverbOpens in new window or a nounOpens in new window.

The symbolic sign of an infinitive is the infinitive marker to  +  base form (root) of verb. For example, “to fly,” to spend,” “to measure,” “to quantify,” or “to report,” etc.

A PRESENT INFINIIVE describes a present condition, as:

The PERFECT INFINITIVE describes a time earlier than that of the verb, as:

The INFINITIVE is often used without to after certain auxiliary verbs, as:

It is also used with to after certain adjectives, as:

It can also be used after nouns, as:


INFINITIVES generally come in two forms:

  1. The to-infinitive = to + base form of verb (to sleep)
  2. The zero or bare infinitive = base form of verb (sleep)

How to Recognize Infinitives

Generally, all infinitives begin with the infinitive marker to followed by the base form (or as also called, the root form) i.e. the basic dictionary form of a verb.


To + verb = Infinitive, as in:

  • to go
  • to play
  • to account
  • to accommodate
  • to ask
  • to report
  • to panic
  • to win

— And so much more. Invariably all the verbs in the English language plus to will form infinitives.


INFINITIVES can take the role of adjectiveOpens in new window, nounOpens in new window, adverbOpens in new window, subject complementOpens in new window, etc. in a sentenceOpens in new window.

1.   An Infinitive as Adjective Modifying a Noun

In the examples below “to aid,” and “to eat,” functions as adjective modifying the nouns ‘laptop’, and ‘lunch’ respectively.

  • Andy installed a computer program in his laptop to aid his project.
  • The boys visit McDonald’s to eat lunch.

2.   An Infinitive as Adjective Modifying a Verb

The infinitives in the example below modifies the verbs ‘want’ and ‘work’ to make a desired meaning expressing the reason for doing the action of the verbs.

  • I love my wife so much, I want to buy her a gift.
  • Everyone work to earn a living.

3.   An Infinitive as Subject of a Sentence

This usually occur in the beginning of a sentence, as:

  • To succeed requires discipline, dedication, and hard work.
  • To sleep in the office is unthinkable.

4.   An Infinitive as Subject Complement

Infinitives can function to complement a subject in a sentence, as in:

  • His favorite leisure is to play with the kids.
  • Andy’s only motivation is to succeed in life.

5.   An Infinitive as Object of a Sentence

Infinitives also serve as object of a sentence as in:

  • She can’t afford to quarrel again.
  • You can as well go to sleep.

6.   An Infinitive as Adjective Complement

Infinitives may also serve as adjective complement as in:

  • Andy seems reluctant to say his mind.
  • I will always be quick to tell her my feelings.