factors ... lead to ----> causes
fail to ----> don't
fall back on ----> turn to
fall back on one's dictionary ----> look up some words
fan ----> like to do sth.
far from being the only one ----> many people
far from new ----> old
fascinating ----> very interesting
faster than ----> exceed
feeble ----> weak
feedback ----> opinion
ferry ----> boat
few ... sit through // out ... entire ----> most ... leave before ... over
few and far between ----> hard to find
figure out // have no idea ----> need one's help
fill in for sb. ----> take the place of sb. // take over for sb. // take over (one's job)
fill in for sb. ----> replace sb. // substitute for sb.
fill one's shoes ----> take one's place
fill out the papers ----> complete the forms
fill sb. in on ----> keep sb. informed of // bring sb. updated/up-to-date on
find ----> look for
find // come up with ----> prepare for
find out about it ----> check on it
fine ----> charge
fine with ----> go along with // agree
finish ----> complete // submit // turn in
finish // put everything together // turn in ----> complete
first start ----> right away
fit as a fiddle ----> in excellent health
five ----> several
fix // take care of // handy ----> repair
fix up ----> work on
float on the air ----> be excited
folks ----> relatives
follow the example of ... ----> follow suit
following the Civil War ----> Post-Civil War
for a while ----> at another time
for more space ----> be well attended
for the third time this month ----> again
forcing the mixture through tiny holes ----> squeezing liquid through small holes
forecast ----> expect
forget ----> not think // quit
form ----> paperwork
forward ----> deliver // send
four o'clock ----> afternoon
four weeks ----> one month
free ----> flexible
free of additives ----> without additives
freeze ----> be very uncomfortable
from ocean beds that dried up long ago ----> in fossils on land
from time to time ----> occasionally // now and then
front-row seats ----> good seats
fun ----> enjoy // enjoyable
function ----> work
furnace ----> heat system