1、used to be 过去曾经是
后面加名词.
例如：I used to be a teacher.我过去曾经是一名老师.
2、used to +动原 过去常常
例如：I used to be afraid of the dark.
我过去常常害怕黑暗.
I used to live in Shanghai.
我过去住在上海.
3、be used to + 动原 被用来做
例如：Elephants can be used to do some heavy jobs.大象可被用来做些重活.
4、be used to +doing 习惯于做某事
例如：I was used to taking a walk at evenings.我习惯傍晚出去散步.