blow, bobble, boggle, bollix (up), boot, botch, bugger (up), bumble, butcher, dub, flub, fluff, foozle, foul up, fumble, goof (up), louse up, mangle, mess (up), muck up, muff, murder, screw up

blunder, gum (up), muddle, piffleblemish, blight, damage, flaw, harm, hurt, impair, injure, mar, mutilate, ruin, spoil, vitiatedestroy, wreckmishandle, mismanage

ameliorate, better, enhance, help, improve, meliorate, rectify, refine, reform, remedydoctor, fix, patch, recondition, renovate, repair, revamp