1.- GERUNDS:
Gerunds are used:
a.- As the subject in a sentence:
Ex: Drinking alcohol is bad for your health.
b.- After these verbs:
Appreciate, Avoid, Detest, Discuss, Enjoy, Finish, Hate, Imagine, Like,
Love, Keep, Miss, Postpone, Practice, Prefer, Resent, Risk, Suggest.
c.- After the following expressions:
It's no use, Be used to, To be worth, Can't help, Look forward to, Get used to, Can't stand, Feel like.
d.- After a preposition:
Ex: I am tired of waiting for you