Commonly Misused Words with Meanings and an Example of Correct Use: From N to Y
naval / navel
naval - to do with the navy
navel - an umbilical or connection to a source, a small scar
The Admiral closely examined the lint from his navel while the naval battle raged around his ship.
prescribe / proscribe
prescribe - to recommend, or dictate behavior or to order the use of a substance
proscribe - to forbid, to eliminate from use, to outlaw
There is an ongoing debate between those who want to proscribe marijuana forever and those who wish to prescribe it for medicinal purposes for cancer patients.
reign / rein / rain
reign - to rule as a monarch
rein - the straps used to control an animal's movement
rain - water falling from clouds
The reign of the beauty queen was cut abruptly short when she lost her grip on the rein controlling her matched team of horses after they slipped in the rain drenched grass.
set / sit
set - to put down, to put in a specific position
sit - to be seated
The finicky man wiped the park bench with his handkerchief and set his unfolded newspaper over the slats before he would sit there.
site / cite
site - a place, a location
cite - to reference or acknowledge a source
The site of the library at Alexandra is no longer anything but an unremarkable burn scar, but many historians still cite it as the greatest collection of lost knowledge in the world, ancient or modern.
then / than
then - to refer to another point in time, a later time
than - to compare things
If the fate of man is to aspire to perfection but never achieve it, then those who never try are no more than dead leaves at the roots of trees reaching toward the sky.
their / they're / there
their - associated with or belonging to
there - where something is
they're - contraction of they are
Many politicians find they're very concerned with the opinions of their home constituents when press conferences are held there.
venal / venial
venal - to be corrupt, to be able to be bought, to bribe
venial - a forgivable sin
When the venal guard took the bribe to give the thieves access to the bank vault, he told himself that it was only a venial sin because no one was hurt.
whose / who's
whose - to whom does it belong (interrogative possessive determiner)
who's - contraction for who is, who has
Who's the careless person whose giant sloth took up residence in the White House rose garden?
won't / wont
won't - contraction of will not
wont - used to doing, habit
Her wont was to spend hours each day on her dress and make-up, and she won't let anyone else into the bathroom until she was done.
your / you're / yore
your - belonging to, a possession
you're - contraction of you are
yore - long ago, in the past
You're the sum of your actions, and they speak louder than your words of yore.
Many of these words were listed in the Wikipedia article on commonly misused words. Others were selected from experience.
If you have some words which regularly confuse you when you try to use them, or you feel should be included, let me know in comments, and I will include them in a future article.