Go on all fours (5)
I believe the answer is:
crawl
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">go on all fours</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for crawl that I've seen before include "Unusually slow rate of movement" , "Grovel" , "Baby-like advance" , "Proceed on hands and knees" , "Slow advance" .)