I got this hat ________; it was very cheap.

1. A.
   on sale
2. B.
   for sale
3. C.
   in sale
4. D.
   at sale

I got this hat ________; it was very cheap.

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根据句意选择适当的词（组）的正确形式填空

be greedy for, take notes, have an effect on, drive off, aim at, in vain, lie in, put out, on sale, live on

I got this hat ________; it was very cheap.