Make improvements (5)
I believe the answer is:
emend
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">make improvements</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for emend that I've seen before include "Alter something written to correct errors" , "change" , "Make improvements to (text)" , "Edit; make alterations to a draft" , "do editorial work" .)