Use oars in line (3)
I believe the answer is:
row
I believe this clue is a double definition.
'use oars' is the first definition.
(I've seen this in another clue)
'line' is the second definition.
(a row or line of things)
'in' is the link.
(Other definitions for row that I've seen before include "Informal quarrel or a straight line" , "Propel with oars" , "Line; squabble" , "Propel boat manually" , "Din; line" .)