过去式 had；过去分词 had；
have
v.有;持有;占有;由…组成;显示出，带有(性质、特征)；
aux.与过去分词连用构成完成时；
第三人称单数 has；现在分词 having
Now she won\'t have to go out to work any more.
现在她不必再出去工作了。
We had a day out in the country.
我们在乡下玩了一天。
A new system has been devised to control traffic in the city.
控制城市交通的新系统已经设计出来。
