bruise

你膝盖上那块淤青是怎么弄的？

How did you get that ___bruise on your knee?

我的胳膊上出现了一个瘀伤。

I have a ___bruise on my arm.

她在桌角撞了一下，手臂上留下了一个小淤青。

She bumped into the table corner and got a small ___bruise on her arm.