Mary is a good girl and she twice(两次) a day.
- A.brush tooth
- B.brush teeth
- C.brushes tooth
- D.brushes teeth
答案
正确答案:D
知识点:动词短语 动词时态:一般现在时

根据主语“she”可判断动词brush要用单三形式brushes,另外“刷牙”需要用到“tooth”的复数形式“teeth”。

略
