(1) I can remember one day when I ………… in class and the teacher said it was time to go home, but I wanted to stay. *

1 used to sit
2 had sat
3 was sitting
4 sitting

(2). I ………… a happy child again. *

1 had become
2 become
3 becoming
4 have become

(3) In the end, I had a fantastic childhood. Now, when I walk past my old school, I remember how much I ………… my time there. *

1 enjoys
2 was enjoying
3 used to enjoy
4am enjoying