我可以说清楚~
填写：Did ,used to
1.used to do something 指的是过去常常做某事,或者过去曾经做某事
此处整句话的意思是甲问：你过去抽烟吗?回答：抽烟,但是我现在已经戒烟了.
因此正确的答案是上面我说的.
2.你提到的be used to ,可以有2种情况.
A.be used to do something.被用来做某事
eg.The knife is used to cut .
B.be used to doing something.习惯于做某事.当然,be used to 后面也可以加名词.
eg.We are used to getting up very late every moring.
He is used to hard work.