Question

used to do的否定句和疑问句

Answer 1

used to do sth. 句型表示“过去常常，过去习惯。”表示过去的某种习惯(过去经常反复发生的动作或状态)。

e.g. I used to live there when I was a child.

n
否定式：used not to do sth.

口语中：didn’t use to do sth.

(used not可缩写为usedn’t或usen’t.)

e.g. I used not to live there when I was a child.

I didn’t use to live there when I was a child.

疑问句：used sb. to do sth.?
Did sb. use to do sth.?
e.g. Used you to live there when you was a child.
Did you use to live there when you was a child?
used to do sth.与be used to (doing) sth.的区别
1. used to do sth. “过去总做某事”(现在不做了)只用于过去时态。
e.g. He used to get up early.
2. be used to (doing) sth. 表“习惯于做某事”，可用于现在、过去、将来的多种时态，be可以用become, get等来代替，此处to是介词。
e.g. He will be used to getting up early.

Answer 2

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