have是什么時(shí)態(tài)用

　　This is too big ─ have you got a small one?

　　這個(gè)太大——有沒(méi)有小的？

　　The latest model has over 100 new features.

　　最新的`款式有100多種新特色。

　　The two groups of children have quite different characteristics.

　　這兩組兒童具有截然不同的特點(diǎn)。

　　Now she won't have to go out to work any more.

　　現(xiàn)在她不必再出去工作了。

　　There have been many changes in recent years.

　　近幾年發(fā)生了許多變化。