问题:
Mary ________ to school by bike when she lived in China.
A.used to go
B.was used to go
C.was used going
D.used to go
Mary ________ to school by bike when she lived in China.
A.used to go
B.was used to go
C.was used going
D.used to go
A.used to go
B.was used to go
C.was used going
D.used to go
参考答案: