Drag behind (3)
I believe the answer is:
tow
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">drag behind</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for tow that I've seen before include "Pull away" , "Draw" , "form of flax" , "Pull along (a vehicle)" , "Prepared fibres" .)