11.Mary ______ to school by bike when she lived in China.

问题描述:

11.Mary ______ to school by bike when she lived in China.
A.used to go B.was used to go
C.was used going

选择A “过去常常”的意思.
而B是过去习惯于的意思,且to是介词.
C没有这种用法.