单词：used to do
音标：[ju:zd tu: du:] ；
过去常常做某事
used to do的用法和样例：
例句
- He used to do a lot of drinking but has signed off now.他过去常常喝酒，但现在戒掉了。
- He used to do such work as he could pick up.他惯常能够找到什么活就干什么活。