Used to

Used to expresses a past situation or habit that no longer exists at present.

Used to menunjukan keadaan atau kebiasaan di masa lampau yang sudah tidak dilakukan di masa sekarang.

Form:
Used to + the simple form of verb
Used to be + the simple form of adjective

For instance:
1.
(+) I used to live with my parents.         Now I live in my apartment.
( -) I did not use to live with my parents.
(?) Did you use to live with your parents?

2.
(+) Ann used to be afraid of dogs, but now she likes dogs.
( -) Ann did not use to be afraid of dogs.
(?) Did Ann use to be afraid of dogs?

3.
(+) Don used to smoke, but he does not anymore.
( -) Don did not use to smoke.
(?) Did Don use to smoke?

4.
(a) I did not use to drink coffe at breakfast.
(b) I never used to drink coffe at breakfast.

Source: Fundementals of English Grammar by Betty Schrampfer Azar