Gerunds and infinitives

A gerund is a noun made from a verb by adding -ing at the end.

E.g:

Playing tennis is fun

Don't confused it with a continuous form!

E.g:

I was playing tennis

I am watching the news

Some common verbs that are followed by gerund are: avoid, enjoy, finish, hate, keep, like, love, don’t mind, prefer, recommend, spend time, stop, suggest, etc.

The negative form of the gerund is not + -ing.

He enjoys not having to wake up early at the weekends. 

Particle 'to' + base form of the verb

BE CAREFUL! 'to' is not a preposition in this case

E.g:

I want to study english