e used to
(1) 被用做..be used to do
The quilt is used to keep warm.
(2)习惯..be/get used to doing
He has got used to new enviroments.
be used for +名词/动名词
The quilt is used for keeping warm.
used to do (did something very often in the past)
过去常做...
He used to go there. But now, he seldom go there.