3º de ESO Inglés

Use to + verb is a regular verb and means something that happened but doesn't happen any more.

It uses -ed to show past tense. But since it always means something that happened in the past, it should always use past tense.

For example-

 I used to go to school in Paris.

When Joshua was a child, he used toclimb trees.

Remember, we always use this word when talking about the past.

So when do you use use towithout the d at the end? When the base form of the verb is used.

Look at these examples- 

She didn't use to swim before noon.

Did your father use to ride a horse? 

In these cases the past tense is shown with the did and didn't.

ALWAYS FOLLOWED BY INFINITIVE.

I used to sleep in my aunt´s bed when visiting her.