4)
was - used to be (бывало, был глупым)
thought- used to think (бывало думал)
hid - used to hide (бывало прятался)
didn't get up - didn't used to get up (я обычно не поднимался пока)
happened - НЕ меняем (единичное действие, не привычка)
6)
2. but I used to tease him when we were younger.
3. but I used to be much busier at work before.
4. but she used to not care about her health before.
5. but he used to smoke a lot 2 years ago.
6. but where did you use to live before?
7. but as a teenager i used to dream of becoming an actor.
used to do/ would do - конструкции, используемые для описания привычных (часто повторяющихся) действий в прошлом и переводятся "бывало" или просто прошедшим временем.