Sentence:  This was going to be it now , any second , and what he had to remember was to <WSD>keep</WSD> his eye on the razor , no matter what , even if Roberts should feint with a kick to the groin , the deadly hand was his exclusive concern . 
Meaning of the word marked with <WSD> tags:  keep in a certain state, position, or activity; e.g., "keep clean"