The infinitive is the name of the verb.

We can also use the infinitive when a verb is followed by another verb... or the gerund, but that, you will find in Unit 10: Verb Patterns. On this lesson, nevertheless, there is a video with a little introduction to those patterns.

VERB + VERB

When an English verb is followed by another verb, the second verb may have three forms:
1- Infinitive with to to dance:    I want to dance
2- Infinitive without to dance:   I can dance
3- -ing form dancing:              I like dancing

Verbs of likes and dislikes (like, dislike, love, hate, prefer, etc) use -ing
Special verbs (can, could, will, would, may, might, must, etc) use infinitive without to
ALL THE REST of the verbs use infinitive with to. Practice this infinitive with the videos in this lesson.

Note: a few verbs can use more than one form, usually with a difference in meaning, for example:
- I prefer walking = I prefer to walk
- I like dancing = I enjoy it, it's great
- I like to visit the dentist = I think it's good

INFINITIVE OF PURPOSE
Another important use of the infinitive is to express the purpose of something:
- I need a key to open this door (why do I need a key? Because I want to open this door)
- I want to marry you to be happy (why do I want to marry you? Because I want to be happy)
- He drinks to forget (he drinks, why? Because he wants to forget)