Question

i'm thinking about ( to go) abroad next summer i'm thinking about going abroad next summer 1- there are many ways of ( to learn) english outside the classroom.2- i'm tired of (to run).let's stop for a few minutes.

Answer 1

I'm thinking about going abroad next summer. 
There are many ways of learning English outside the classroom.
I'm tired of running. Let's stop for a few minutes.

Quando temos uma preposição (of, about, without, at, with, on, in,...), normalmente, o verbo que vem na sequência termina com -ing.