accede, exceed

Accede means to agree, to allow; exceed means to go beyond, to surpass, as in
“Drivers who exceed the speed limit are asking for hefty fines.”
accept, except

Not commonly seen even from unpublished writers, who are probably familiar with the difference because they’re all waiting for an acceptance!
“We accept your invitation to your party, except for Bill, who will be away on that day.”
However, I recently saw (on a publisher’s web site!) the statement, “We are excepting submissions … ” Can you believe it?

adapt, adept, adopt

Adapt means to adjust, adept means skilled and adopt means to take as your own:
“Some people cannot adapt to new surroundings.”
“He is very adept at dodging awkward questions.”
“He tends to adopt the attitudes of those around him.”

addition, edition

I saw this confusion on a review on amazon.com—“a nice edition to the series”. Obviously the writer meant addition. However, if one person can get these confused, maybe others do too. Addition is something that is added; edition is a particular version, issue or publication of a book, play, etc.
adverse, averse

Adverse means inauspicious, hostile; averse means disinclined, repelled.
“I’m very much averse to making a long, arduous journey under such adverse weather conditions.”
advice, advise

Advice is the noun and advise the verb.
“His advice was that we should advise everybody to either stay away or be extremely careful.”

affect, effect

Affect is a verb; effect is more usually a noun. When used as a verb it means to achieve, fulfill, realize.
“Bad weather will affect the quality of the fruit.”
“The effect of bad weather is a reduction in fruit quality.”
I can’t think of any sentence using effect as a verb where one of the other three mentioned above would n’t be a much better choice, but perhaps a politician might say, “To effect our goal of saving 10%…”
aloud, allowed

Aloud means out loud, speaking so that someone else can hear you; allowed means permitted.

altar, alter

Altar is the table in a church; alter means to change.

already, all ready

Already means by this time; all ready means prepared.
“Are you already packed?”
“Yes, I’m all ready to leave.”
altogether, all together

Altogether means wholly; all together means everybody in a group:
“It’s altogether too bad that you can’t come.”
“All together, now: ‘Good morning, Sir!’”
all right, alright

All right is the correct form; alright is grammatically incorrect.
allude, elude

Allude means to refer to; elude means to dodge or escape.
allusion, illusion

Allusion is an indirect reference or hint; illusion means deception or mirage.
all ways, always

All ways means by every way or method; always means all the time, forever.

amoral, immoral

amoral describes someone who has no morals; immoral describes someone with low morals.

annual, annul

Annual means yearly; annul means to make void or invalid.
anyone, any one

This is quite tricky. Anyone means anybody, any person at all; any one means any one person and is followed by “of”.
“Does anyone else want to come?”
“Any one of you is welcome to come along.”
appraise, apprise

Appraise is to assess or estimate. Apprise is to inform or notify:
“I will appraise the situation and immediately apprise everybody of my conclusions.”
Please don’t make your character say or write anything like this, though—unless you want him to sound like a pompous twit!
ascent, assent

Ascent is an upward movement; assent means agreement.

assistance, assistants

Assistance means help or aid; assistants is the plural of assistant, one who gives help.
assure, ensure, insure

Assure means to guarantee; ensure means to make sure; insure means to protect against loss or damage:
“I assure you there’s no call for alarm.”
“To ensure your crockery does nt get broken, wrap it all in bubble wrap.”
“In case of breakage or loss, you should insure everything with a good insurance company.”
auger, augur

Auger is a tool; augur means to predict.

bore, boar, boor

Bore as a noun is a boring or tiresome person, or something that you don’t like doing; it can also be used to refer to something used for drilling (e.g., an oil bore). As a verb it also means to drill; boar is a male pig; boor is a vulgar person.
board, bored

Board is a long sheet of wood, also a group of people as in “Board of Directors”, and as a verb means to go onto a ship, plane or other form of public transport; bored means not interested.
born, borne

Born is always the beginning of life, borne means carried.
“I was born in the middle of a particularly severe winter.”
“The logs were borne down the river to the mill.”
bought, brought

Bought is the past tense of buy, brought is the past tense of bring. So, I bought (paid for) a load of topsoil, and a truck driver brought (delivered) it to my home.
braise, braze

Braise means to cook slowly in liquid (usually meat); braze most commonly means to solder with an alloy of copper and zinc.
brake, break

Brake means to stop; break means to smash.
bridal, bridle

Bridal has to do with brides and weddings; bridle as a noun means a halter or restraint; as a verb it means to restrain or to draw oneself up in anger.
by, buy, bye

By is a preposition meaning next to; buy means purchase; bye means farewell or good-bye.
canvas, canvass

Canvas is cloth or fabric; canvass means to seek votes, to survey, to sell door-to-door.
capital, capitol

Capital means the seat of government; money invested; excellent, as in “What a capital idea!”. Capitol is the building where government meets, although in New Zealand that’s simply called The Beehive.
caught, court

Caught is the past tense of catch. Court is a place where criminals are tried; a place where ball games are played; a royal household or residence. As a verb it means to curry favour, to strive for or seek; or (in relationship terms) to date someone of the opposite gender.
cereal, serial

Cereal is something you might eat for breakfast, such as porridge. Serial is something in a series; something that continues one after another, as in a weekly instalment of chapters from a book.
censor, sensor

Censor as a verb means to officially inspect and make deletions or changes (in books, letters, movies, etc.) usually because the deleted or changed material is regarded as offensive or harmful in some way, though movies these days are more likely to be given a rating instead; as a noun it refers to the official who does the censoring. Sensor is something that senses (for instance a burglar alarm has many sensors: for movement, body heat, etc.)

coarse, course, cause

It didn’t occur to me that these could be confused until I saw “of cause” instead of “of course”. Coarse means rough-textured or scratchy; large (as in coarse gravel); heavy and ugly (as in coarse features); loutish, vulgar, crude, improper. Course (apart from its use in “of course”) is a noun meaning: route, track, a raceway; progression, development; plan, plan of action; a programme of study; a schedule or sequence. Cause as a noun means origins, beginnings; grounds, justification; an ideal or belief; a case or lawsuit. As a verb it means lead to, result in, make happen.

collaborate, corroborate

Collaborate means to work with someone; corroborate means to establish the truth of something.
compliment, complement

Compliment means praise or congratulate. You always pay someone a compliment, not a complement. Complement means to supplement, round out. Mustard complements ham, for instance, by “rounding out” the flavour.
continual, continuous

Continual means something that happens frequently, with breaks between the occurrences. Continuous means something that happens without stopping!
“Continual interruptions distract me from writing.”
“The continuous noise of the motor mower distracts me from writing.”
co-operation, corporation

Co-operation (usually spelt without the hyphen in US English) means working together; corporation is a business organisation.
copyright, copywrite

Copyright is the legal ownership of a book, film, play, piece of artwork, musical composition, etc, or the right to print, publish, film, record or perform them; copywrite is something you do if you are creating advertising or publicity material.
correspondence, correspondents

Correspondence is written communication; correspondents are those who write it.
creak, creek

Creak is both a noun and a verb and means squeak or groan (for instance, rusty hinges and loose floorboards creak); creek is a noun and means a waterway or stream.
credible, creditable

Credible means believable; creditable means praiseworthy or deserving credit.
criteria, criterion

Criterion is singular; criteria is plural.
curb, kerb

Curb means to control, as in “curb your temper”, while kerb is the edge of a footpath or sidewalk.
currant, current

Currant is a fruit, usually dried. Current as an adjective means contemporary, fashionable; as a noun it means stream, flow.

desert, dessert

Desert means to abandon (and can also be a noun, meaning a wasteland); dessert is the sweet course of a meal.
device, devise

Device is a noun, meaning a gadget or (particularly in writing terms) an invention; devise is a verb, meaning to invent or plot.
discreet, discrete

Discreet means respectful, prudent; discrete means separate or detached from others.
draft, draught

Draft refers to the first writing of your novel or story (or any other document). You can also be drafted (enlisted or recruited) into the army, navy, etc.
Draught is an air movement, a drink (as in “draught of ale”) or refers to a horse (or other animal) used for pulling ploughs, etc (e.g., “draught horse”).
elicit, illicit

Elicit means to extract or draw out; illicit means not legal.

eminent, imminent

Eminent means distinguished, famous; imminent means near, close at hand.
everyday, every day

Everyday means commonplace, ordinary; every day is used for something that happens daily.
everyone, every one

Everyone means every person in a group; every one means each person and is always followed by “of”.
“Everyone needs to know how to swim.”
“Every one of you should be able to swim.”
fair, fare

Fair means average, good-looking, pale, unbiased (what a lot of meanings for one little word!); fare is the money you pay to go somewhere by bus, train, plane, taxi, etc. It can also refer to a passenger. As a verb it means do, as in:
“I didn’t fare as well in my exams this year as I’d hoped.”
farther, further

Farther is used for physical distance; further for non-physical. For instance:
The farther we walked the more hostile the terrain became.
I promised to give the plan further thought.
faze, phase

The most common error is the use of phase when the writer means faze. To faze someone is to fluster or confuse them, whereas phase is mostly used in reference to a stage in someone’s life—though it can be a stage in almost anything else:
“Like most children, Danny’s going through a phase of refusing to eat his vegetables.”
“Nothing fazes my mother, who can produce a meal for unexpected guests at a moment’s notice.”
flare, flair

Flare means to flash or blaze and (as a noun) is a pyrotechnic device; flair means ability or skill.
forbear, forebear

Forbear means to refrain from; forebear is an ancestor or forefather.
foreword, forward

Foreword is the preface in a book, usually written by someone who is not the author; forward means ahead, near the front.
forth, fourth

Forth means forward; fourth is after “third”.
foul, fowl

Foul can mean dishonourable (by foul means), disgusting (a foul smell), entangle (rubbish dumped in the river can foul fishing lines); fowl is a bird.
found, founded

Found is the past tense of find; founded means started, as in “My great grandfather founded this company nearly a hundred years ago.”
gibe, jibe

Gibe means to taunt; jibe means to agree, correspond or tally; in boating it means to shift the sails.
gorilla, guerrilla

Gorilla is a large ape; guerrilla is a particular kind of soldier.
hail, hale

Hail means to greet or to come from (as in “She hails from Texas”) and as a noun it is frozen raindrops; hale means healthy or (as a verb) to haul.
hanged, hung

A criminal is always hanged; a picture is hung:
“We hung the portrait where everybody could see it.”
“John Smith was hanged yesterday at dawn.”
Just remember, “I’ll be hanged if they’re going to hang me,” and you won’t forget the difference again!
herd, heard

Herd is a group of animals; heard is the past tense of hear.
here, hear

Here refers to a location (as in “over here”). Hear is always what your ears do. I can’t see why writers should get confused here, but they must do because I have seen this more than once. (And, no, that’s not a sample sentence!) I’ve even seen “Here! Here!” when the writer wasn’t having a character call another character, but was expressing support for a real person!
hoard, horde

Hoard means to stockpile and as a noun it is a cache of stockpiled stuff; horde is a large group.
hole, whole

Hole is an opening; whole means complete.
home, hone

In this case the error is always using “hone in” instead of “home in”. Hone means to sharpen.

idle, idol

Idle means inactive, lazy; idol is something that is worshipped or (in the case of a person) looked up to as a hero.

immemorial, immortal

Immemorial means ancient beyond memory (as in the cliché “since time immemorial”); immortal means deathless, eternal.

incite, insight

Incite is a verb that means to stir up; encourage: “Talk like this is likely to incite a riot.” Insight is a noun meaning intuition; awareness; understanding.
intolerable, intolerant

Intolerable means tiring, onerous crushing; intolerant means biased, prejudiced. Someone cannot be intolerable of another’s beliefs.
irregardless, regardless

There is no such word as irregardless; the correct word is regardless.

its, it’s

This is confusing because possessives normally have an apostrophe, but in this case it’s is short for it is and its is possessive—always.
“Its color is green and it’s quite beautiful.”
Other possessives that don’t have an apostrophe are theirs, hers, yours and his—though I doubt anyone is likely to try putting one in his!
knew, new

knew is the past tense of know; new is the opposite of old.
later, latter

Later means afterwards; latter is the second of two things.
“Later that day we went for a walk.”
“We have two choices. The latter is the more reliable, but the former would be cheaper.”
lay, laid

This pair confuses writers almost more than any other.
“He lay on his bed.” Although this sentence is past tense, “laid” would be incorrect and suggests he was laying eggs.
“She sighed as she laid the visitors’ book beside the pen and lay back wondering if she would ever make an entry in it again.”
In present tense the sentence would read, “She sighs as she lays the visitors’ book beside the pen and lies back, wondering if she will ever make an entry in it again.”
BUT “I sigh as I lay the visitors’ book beside the pen and lie back, wondering if I will ever make an entry in it again.”
(In practice, I would probably write I place/placed and she places/placed. It’s so much less confusing, not to mention less repetitive!)
“It lay on the desk beside an open book.” Present tense would read, “It lies on the desk beside an open book.”
“Our hens lay every day.”
“The hens laid ten eggs yesterday.”
lay, lie

When these two are confused it’s usually because the writer is in the wrong tense for a word that means recline. “I am going to lay down because I don’t feel well” or “I am going to lay on my bed and read” are both incorrect; the word should be lie. In the second sentence it sounds as though the writer is going to lay an egg as well as read! In past tense, however, the correct usage is “I lay down because I didn’t feel well” and “I lay on my bed and read”.
lead, led

Lead (pronounced led) is a heavy metal or (pronounced leed) the present tense of led. So:
“He opens the door for me and I lead the guests upstairs to their rooms.”
“He opened the door for me and I led the guests upstairs to their rooms.”
lend, loan

Lend is a verb meaning to give something temporarily to someone; loan is a noun, meaning the temporary transfer of something to someone else. So, “Dad, can you loan me a few dollars until pay day?” is incorrect.
lessen, lesson

Lessen means to make less; lesson is something you learn.
liable, libel

Liable means subject to, answerable for or likely; libel is written (as opposed to spoken) untruths about someone, for which you may be taken to court.
“He is liable to sudden attacks of ill temper for no apparent reason.”
“Politicians should be made liable for their bad decisions.”
“Pollen is liable to cause hay fever or even asthma attacks in certain individuals.”
licence, license

In British usage, licence is always the noun and license the verb.
lightening, lightning

Lightening means making lighter or brighter; lightning (which is always a noun) is what comes out of the sky, usually followed by a crack of thunder.
lose, loose

Lose always means mislaying or dropping something and not being able to find it, while loose means slack or free:
“If the fastening on your wrist-watch is loose (slack) you may lose your watch.”
manner, manor

I saw this pair confused in an email (“all manor of complaints”) and figured if one person could get them confused others could too. Manner means method, appearance, class, character; manor is strictly a large, stately house.
mantel, mantle

Mantel is the shelf above a fireplace, or the fireplace surrounding; mantle is a cloak or blanket.
marshal, marshall

Marshal is a military officer or a sheriff; marshall is a verb meaning to muster, usher, guide; align, array, organize.
maybe, may be

Another tricky one, best explained by demonstration:
“Maybe you could explain this to us a little clearer.”
“It may be a good idea to give us a clearer explanation of this.”
meet, mete, meat

The two more often confused are meet and mete. Meet means to encounter (and can also mean fit or suitable); mete means to allot, apportion or distribute; meat refers to flesh as food.

moat, mote

Somebody found this confusion in Twilight by Stephenie Meyer. Moat is a deep, wide ditch surrounding a castle, fort or town. Usually filled with water, it is intended as a defense against attack. Mote is a tiny piece of substance, as in motes of dust that can show up in a sunbeam. Apparently Meyer had written “dust moats”.

mute, moot

Mute as a verb means to silence or quieten down, as a noun it’s a little gadget used by string players (particularly violinists) to soften the sound from their instruments. As an adjective it means dumb or making no sound, as in “He looked at me in mute appeal.” Moot means debatable. So, it’s a “moot point” not a “mute point”.
no, know

Strange that these two should get confused, but they do. No is always the opposite of yes; know is to be certain (that you know the difference!)

none, nun

I could hardly believe my eyes when I read “and nun at the top” instead of “and none at the top”. A nun is strictly a woman belonging to a religious community. When you mean “not any” the spelling is none.
overdo, overdue

It baffles me that people get these mixed up, but they do. Overdo means to exaggerate or carry something too far; overdue is what your bills are when you forget to pay them!
passed, past

Passed is the past tense of pass. Past means a time that has gone.
“Time passed and we all forgot the incident.”
“In times past it was the custom for women to wear hats in church.”
"I passed him at the crossroads; he went past at a stagger."

peace, piece

Peace means the absence of war (or even noise); piece is a portion of something.
pedalled, peddled

Pedalled is the past tense of pedal, which as a verb means to use your feet to turn the pedals on something, such as a bicycle, to make it move; or to operate the sustaining and/or soft pedals on a piano, or the lower keys on an organ; peddled is the past tense of peddle, which means to sell.
peer, pier

Peer as a noun means a person who is your equal and as a verb it means to squint or look obliquely at something; pier is a type of wharf or dock. Two other words that sound similar are pear (a fruit) and pare (to peel) but I haven’t seen any instances where these have been confused.
plain, plane

Plain means obvious, also unadorned or lacking in good looks; plane is a carpenter’s tool or an abbreviation of aeroplane.
patience, patients

Patience means forbearance; patients are people under medical care.
peek, pique, peak

Pique means to excite or irritate; peek means to peep or snoop; peak as a noun means the summit or tip, and as a verb means to climax. So, you pique someone’s curiosity; you don’t peek or peak it. If someone annoys you, you become piqued rather than peeked or peaked.
perspective, prospective

These two sound only vaguely alike yet seem to get confused. Perspective means point of view; also panorama; prospective means future, inevitable, destined.
pour, pore, poor

You pour sauces, gravies, etc, over your dinner, while pore means to study something—so, “pore over the book”, not “pour over the book”, which reads as though you might be damaging the book with an unnamed liquid substance! Poor is what you are when you don’t earn enough money, but I’ve seen it used when the writer meant pour.
practice, practise

In British usage, practice is always the noun and practise the verb.
pray, prey

Pray is usually what you do when you talk to God; prey as a verb means to hunt, to stalk,; as a noun it means the subject of the hunt.
premise, premises

Premise usually means assumption, supposition, while premises means an apartment, house or building and its grounds.
presence, presents

Presence means being near at hand; presents are gifts.
principal, principle

Principal means chief or main, also the amount borrowed in a loan; principle means regulations or ideals.
“The principal reason for the company’s failure was lack of money.” (or)
“The new principal is making a real difference to our school.”
“We are paying both principal and interest each month on our mortgage.”
“She is completely without principles and would steal from her own mother.”
“The principle of a clause like this in your employment contract is to protect you against unfair dismissal.