我把门钥匙挂在钥匙圈上，这样就不会丢了。

I keep my ___latch-key on a key ring so I won't lose it.

她是个钥匙儿童，在父母下班回家前都自己照顾自己。

She is a ___latch-key child who takes care of herself before her parents come home from work.