Affirmative statements: S + used to + verb base +.....
Negative statements: S + didn't + use to + verb base + ....
Yes/No Questions: Did + S + use to + verb base + .....
Wh questions: Wh -did + S + use to + verb base + ....
We use used to when we refer to things in the past that are no longer true. It can refer to repeated actions or to a state or situation:
He used to play football for the local team, but he’s too old now.
That white house over there used to belong to my family. (It belonged to my family in the past, but not any more.)
Other information about "used to"..click here.
Click here to practice using "used to".