have后面加什么时态
have作为助动词，只出现在现在完成时中，并且在动词之前构成完成时，比如
我已经完成了作业
I have finished my homework.
The two groups of children have quite different characteristics.
这两组儿童具有截然不同的.特点。
Now she won\'t have to go out to work any more.
现在她不必再出去工作了。
There have been many changes in recent years.
近几年发生了许多变化。
Call me if you have any problems regarding your work.
你如果还有什么工作方面的问题就给我打电话。
No new SARS cases have been reported in the region.
该区没有新增非典型肺炎病例。
You will always have the bad as well as the good in the world.
人生在世总是有苦有甜。