Do 的四作用

　　动词do在句中的作用可以概述为四句十二字："做"实义，助动词，替前文，强语气。

　　作用一：实义do

　　do作实义动词时，有do, does, did, done, doing五种形式，还有及物、不及物之分。如：

　　1. vt. "做；研究；整理；完成"。如：

　　①The old man does an hour of sport every day.

　　②She did her homework at home last night.

　　③Mother was doing the cooking when I reached home.

　　④Have you done the exercises yet?

　　2. vi. "行动；工作；进展；足够"。如：

　　①Kate does very well in her Chinese.

　　②How do you do?

　　③Well done!

　　④That will do.