鑰匙在門上用in。in雖然也翻譯為在門上，但鑰匙是插在門里面，所以用in。例如，The key is in the door。

in the door例句

They put the key in the door and entered.

他們用鑰匙打開門進(jìn)去了。

I looked everywhere for my keys and they were in the door all the time.

我到處找鑰匙，沒想到鑰匙一直插在門上。

The key turned in the door, and I could hear the feet of the guards outside.

鑰匙插在鎖孔里，我可以聽到外面衛(wèi)兵的腳步聲。

on the door例句

They had put a padlock on the door of his flat.

他們已經(jīng)在他的公寓門上上了把掛鎖。

There was an old rusting bolt on the door.

門上有一個生銹的舊門閂。

The lock on the door is rusty and won't open.

門上的鎖銹住了。