我知道她生我的气，但我并不为此担心。

I know she's angry with me, but I'm not ___losing any ___sleep ___over it.

我简直太忙了，没时间为此担心。

I was simply too busy to ___lose any ___sleep ___over it.

他常常为工作上的小问题担心。

He tends to ___lose ___sleep ___over minor issues at work.