not happy
unhappy
not lucky
unlucky
untie
not tie
unclean
not clean
unlock
not lock
unkind
not kind
preschool
before school
pay before
prepay
mix before
premix
prewrite
write before
test before
pretest
dislike
not like
disobey
not obey
not agree
disagree
dishonest
not honest
disappear
not appear
