V: 1, I used to live on a farm
2, Ben used to drink a lot of coffee, but now he prefers tea
3, I used to go to school by bike when I was young
4, She used to be rich three years ago
5, Mr. John used to work hard
6, She used to get up late when she was young
7, My father used to smoke
8, We used to have lots of friends when we lived in the country
9, There used to be some old banyan trees one hundred years ago
10, There used to be some trees in the field
11, She used to live with her parents 
12, I used to walk to school

CT: used to+V-bare: đã từng