from time to time

for the time being

fury

furnish

for the sake of

for good

fuss

fulfill

frown

frustrate

frequent

fracture

formulate

forge

forbid

flush

fluctuate

flourish

fling

for the better

flexible

flatter

flee

flat

flavor

flash

flare

figure

feed

feeble

finite

feasible

finance

favor

fashion

fascinate

fare

fancy

faint

fade

facilitate

fabricate

fall off

fall through

fall out

fall in with

fall behind

find fault

fall in love with

flare up

fill in

from now on

feed into