他们用毯子盖住了沙发上的污渍。

They used a blanket to ___cover ___up the stain on the sofa.

他试图通过责怪他人来掩盖自己的错误。

He tried to ___cover ___up his mistake by blaming others.

我们需要在粉刷房间前把家具盖起来。

We need to ___cover ___up the furniture before painting the room.