(1) used to do sth. 过去常常……(现在已不如此)
We used to grow beautiful roses.
You usedn’t to make that mistake.
She didn't use(d) to do it, did she?
You used to smoke a pipe, didn't you? / use(d) n't you?
(2) be / get / become used to + n. / doing 习惯于
I have always been used to hard work.
He got used to living in the country.
(3) be used to do 被用来做……
This knife is used to cut bread.
(1) would 只强调“过去常常……”，used to 说明现在不是如此。
The old woman would sit there for hours doing nothing.
(2) would 只接行为动词，used to 可接行为动词和表状态的词。如：be, like, know, have。There used to be a temple at the foot of the mountain.