four

four days running

four-poster bed

four-leaf clover

to be a four-eyes

four weeks

fourteen

fourteen days

fourth place

fox/foxy lady

Foxhunting dominates [the] public debate in England

fraction

by a fraction of an inch

fraidy-cat

Frailty, thy name is woman!

to frame a rule

to frame an answer

to frame someone

to frame

frame of mind

Be frank with me

frankenfish

Frankly, he's not much of a boss.

frantically

fraternal twins