used to do sth.过去常常做某事,(意思现在不做了)
    例:  I used to get up early and take an hour's walk before breakfast.
           我过去常常起床很早并且在早餐前散步一小时.
2.be used to doing sth  / be used to sth .是指习惯于做某事.(这里的to 是介词.)
   例:     She isn’t used to living in the countryside now.
             她不习惯在乡下生活.
       Are you used to the food here?
              你习惯吃这儿的饭菜吗?
       
3.be used to do sth.被用来做某事
  例:      Computers are used to do many things for people now.
               现在计算机被用来做许多事情.3Q3q