Translation of "Accidentally" in Chinese

I accidentally mistakenly took his umbrella.

我不小心拿錯了他的傘。

He hurried out the door, and accidentally forgot the key at home.

他匆匆忙忙地出門，不小心把鑰匙落在家裡。

Manholes are round because that way they won't accidentally fall through the hole.

人孔是圓的，因為這樣人孔蓋就不會意外地掉進洞裡。

Maybe at the time she accidentally left her car key in her room.

也許當時她將車鑰匙忘在自己的房間裡了。

- She may have left her car key in her room.
- Maybe at the time she accidentally left her car key in her room.

也許當時她將車鑰匙忘在自己的房間裡了。