have的过去式和过去分词是什么给点例句。。

have的过去式和过去分词都是had，但是具体应用有区别。

1. 表示过去用过去式：We had a meeting yesterday .(发生在过去)。

2. 表示现在完成（助动词的现在式+过去分词）：We have had a meeting just now.(虽然发生在过去，却对现在产生了影响，即会议的进程在说话时依然清晰可见)。

3. 表示过去完成（助动词的过去式+过去分词）：We told him we had had a meeting the day before yesterday.（发生在told的过去，即过去的过去）。

has

1、This is a clear demonstration of how technology has changed?

这清楚地表明了技术已有了怎样的进步。

2、There has already been a definite improvement?

已经有了显著的改进。

3、The committee has been dissolved?

委员会已经解散了。

4、She enchanted you as she has so many others.?

她迷住了你，就像她迷住了其他那么多人一样。

5、The conflict with James has dragged on for two years.?

与詹姆斯的冲突拖了两年。