Learn how to use Infinitives in English with rules and examples.
You can jump to any section of this lesson:
- 1 What is a To-Infinitive?
- 2 Functions of Infinitives
- 3 Grammar Rules to Master the Use of Infinitives | Picture
What is a To-Infinitive?
A to-infinitive is a verbal consisting of to + a verb, and it acts like a subject, direct object, subject complement, adjective, or adverb in a sentence. Infinitives are easy to identify because they’re written with to + a verb.
Although an infinitive is easy to locate because of the to + verb form, deciding what function it has in a sentence can sometimes be confusing.
Functions of Infinitives
We use the infinitive:
To indicate the purpose of an action
He bought some flowers to give to his wife.
I will lock the door to prevent theft.
As subject of the sentence
To wait seemed foolish when decisive action was required.
To swim in that sea may be dangerous.
As direct object of the sentence
I like to write in English.
Everyone wanted to go.
As subject complement
His ambition is to fly.
What is essential is to maintain a healthy diet.
As an adjective
This is the best time to practice.
I have some jeans to wash.
As an adverb
We must carefully observe to understand.
I can’t wait to see.
Subject + to be + adjective + (for/of someone) + to-infinitive + (rest of sentence)
It is important to be patient.
It is wonderful to have close friends.
After object that is noun or pronoun referring to a person
Can I ask you to help me with something?
I invited a friend to attend the ceremony.
Used with question word
Do you understand what to do?
Tell me when to press the button.