have的过去式是什么

例句：

They had had their pet dog stuffed.

他们请人把他们的宠物狗制成了标本。

She had repented of what she had done.

她对自己所做的事深感懊悔。

Everything had gone.

一切都过去了。

The car had had it.

这辆车无法修复了。