un-, non-

not, opposite of

re-

back, again

sub-

under, below

pre-

before, in front of

semi-

half, partly

mid-

middle

de-

down, away from

anti-

against, opposite

pro-

before, forward, infavor of

ex-

out, away from

per-

through or completely

con-

together, connect, or with

dis-

not, apart, away

mis-

bad, wrong, to hate

circ-, circum

around, circle

bi-

two, twice

tri-

three, third