1- Infinitives are the "to" form of the verb.
The infinitive form of "learn" is "to learn." You can also use an infinitive as the subject, the complement, or the object of a sentence.
· To learn is important.
· The most important thing is to learn.
· He wants to learn.
2- Infinitives can be made negative by adding "not."
· I decided not to go.
· The most important thing is not to give up.
3- Some verbs are followed by infinitives
4- Some verbs are followed by a noun +infinitive.
In some situations, the noun is required. In other situations, the noun is optional.
· The police ordered the man to stop. (noun is required)
· She asked to leave. (noun is optional)
· She asked him to leave. (noun is optional)
Reading helps you learn English.
(SUB) (VERB) (OBJECT)
Her favorite hobby is reading.
(SUBJECT) (Verb) (COMPLEMENT)
I enjoy reading.
(S) (V) (O)
The best thing for your health is not smoking.
He prefers not speaking.
3-In the subject position mostly gerunds are used.
Learning is important.
Dancing is enjoyable.
4- Some verbs are followed by gerunds as objects.
5- There are many "go + gerund" expressions used for adventure sports and individual recreational activities
6- Gerunds are used after prepositions.
Sandy is scared of flying.
They admitted to committing the crime.
7- Gerunds can often be modified with possessive forms such as his, her, its, your, their, our, John's
I enjoyed their singing.
She understood his saying no to the offer.
Sam resented Debbie's coming late to the dinner.
We discussed Mary’s behaving so rude.
GERUND OR INFINITIVE ?
Some verbs can be followed by a gerund or an infinitive, but with a difference in meaning.