1.   Anything could knock him off his perch.

2.   Bluechel, unharmed, fled the scene, a bullet knocking off his cap as he ran.

3.   By five he had knocked off most of the items on his priority list.

4.   Do you want to knock off early today?

5.   He was knocked off his bicycle on his way home from a shopping trip.

6.   Here the X-rays knock off chlorine atoms one after another until there are only VOC-like compounds left, which are finally destroyed.

7.   I have always been able to knock off twenty years.

8.   Is it OK if I knock off a little early tonight?

9.   Roland makes a lot of money knocking off copies of famous paintings.

10.   She could have knocked off a thousand words on the pocket combs alone.