used to do和be used to doing的含义不同，be used to doing表达习惯于做某事的意思；used to所表示的意思是“过去常常做某事”，强调过去发生的事，所以一般用于描述发生在过去的事情。
used to do的否定形式是didn&39;t use to do 或 usedn&39;t to do；疑问形式是Did you use to do sth?
例句：My brother used to go swimming in the sea.我哥哥过去常常在海里游泳。否定形式是My brotherdidn&39;t use to go swimming in the sea.
疑问形式是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.
我习惯于早上喝一杯茶。
