agonize over
alternate
back and fill
be all thumbs
be at sea
be hard put
be uncertain
beat about
blunder
blunder away
blunder into
blunder on
blunder upon
boggle
botch
bumble
bungle
butcher
capsize
careen
career
come a cropper
commit a gaffe
doubt
ebb and flow
fall
fall down
fall flat
fall headlong
fall over
fall prostrate
falter
faux pas
feel unsure
flounce
fluctuate
fumble
get a cropper
go through phases
grope
grovel
have trouble
heave
hobbyhorse
labor
labor under difficulties
list
lumber
lurch
fight
flatfish
struggle
walk
floundered
floundering
flounders
bounder
cofounder
founder
grounder
pounder
rounder
sounder