Chew like a beaver (4)
I believe the answer is:
gnaw
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">chew like a beaver</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for gnaw that I've seen before include "Wear away with the teeth" , "Chew steadily at" , "Nibble; cause anxiety" , "Bite persistently, grind" , "Chew persistently at, say a bone" .)