| Affirmative | used to + V: the same for every subject | She used to live in Rome. |
| Negative | didn't use to + V | We didn't use to have a car. |
| Question | Did + subject + use to + V | Did you use to walk to school? — Yes, I did. |
| Use | past habits and states that are over now | I used to walk to school. / We used to have a dog. |
| Past simple | a single event, or a stated time or number | I lived in Paris for two years. |
| Position | always, often and never go before used to | He always used to be late. |
| Sound | the d is silent: used to sounds like use-ta | I used to swim. |
| Trap | the affirmative keeps the d: used to | I used to play football. |
| Trap | after did and didn't the d goes: use to | I didn't use to like it. |