①used to do 过去尝尝做某事，例如，He used to swin in the river when he was a child. 当他是小孩时，他经常在小河里游泳。

② be used to do 被用来做某事。 Woods can be used to make paper.木头能用来造纸。

③ be used to doing.习惯做某事。 My mun is used to walking after supper.我妈妈习惯晚饭后散步。