We should brush our teeth ________ .

1. A.
   two time a day
2. B.
   twice a day
3. C.
   twice days
4. D.
   twice day

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1根据所给英文写出单词的合适形式。

1.Lily is a good         (swim) because she is the first in the swimming match.

2.We usually brush our teeth           (two) a day .

3.I have a little dog .            (it) nose is white.

4.How long do you spend             (chat) with your e-friends on the Internet every day?

5.Fruit and vegetables are             (health) food.