used to do和be used to doing的区别

used to do的否定形式是didn't use to do 或 usedn'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'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。