used to do和be used to doing的含義不同,be used to doing表達習慣于做某事的意思;used to所表示的意思是“過去常常做某事”,強調(diào)過去發(fā)生的事,所以一般用于描述發(fā)生在過去的事情。

used to do的否定形式是didn't use to do 或 usedn't to do;疑問形式是Did you use to do sth?
例句:My brother used to go swimming in the sea.我哥哥過去常常在海里游泳。否定形式是My brotherdidn't use to go swimming in the sea.
疑問形式是Did your brother use to go swimming in the sea?
be used to doing的例句:I am used to having a cup of tea in the morning.
我習慣于早上喝一杯茶。