问题补充：
My cousins me and ask me what I was doing when I was studying in Canada.
A. used to ringing
B. were used to ring
C. were used to ringing
D. used to ring
答案：
A. used to ringing
B. were used to ring
C. were used to ringing
(答案→)D. used to ring
解析：词义辨析。Be used to do sth 被用来做某事；be used to doing sth 习惯于； used to do sth 过去常常。 我在加拿大学习时我的堂兄常打电话问我在干什么？ 根据语境选D
