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Spelling: Common Words that Sound Alike


This resource covers common spelling errors including accept/except, ei/ie, noun plurals, and –ible/able.

Many words sound alike but mean different things when put into writing. This list will help you distinguish between some of the more common words that sound alike. Click on any of the blue underlined links to open a longer and more complete definition of the word in a new window.

Forms to remember

Accept, Except

  • accept = verb meaning to receive or to agree:
    He accepted their praise graciously.
  • except = preposition meaning all but, other than:
    Everyone went to the game except Alyson.

We are currently updating these resources, but for more information on these words, plus exercises, see our document on accept and except.

Affect, Effect

  • affect = verb meaning to influence:
    Will lack of sleep affect your game?
  • effect = noun meaning result or consequence:
    Will lack of sleep have an effect on your game?
  • effect = verb meaning to bring about, to accomplish:
    Our efforts have effected a major change in university policy.

A memory-aid for affect and effect is RAVEN: Remember, Affect is a Verb and Effect is a Noun.

We are currently updating these resources, but for more information on these words, plus exercises, see our document on affect and effect.

Advise, Advice

  • advise = verb that means to recommend, suggest, or counsel:
    I advise you to be cautious.
  • advice = noun that means an opinion or recommendation about what could or should be done:
    I'd like to ask for your advice on this matter.

Conscious, Conscience

  • conscious= adjective meaning awake, perceiving:
    Despite a head injury, the patient remained conscious.
  • conscience = noun meaning the sense of obligation to be good:
    Chris wouldn't cheat because his conscience wouldn't let him.

Idea, Ideal

  • idea = noun meaning a thought, belief, or conception held in the mind, or a general notion or conception formed by generalization:
    Jennifer had a brilliant idea—she'd go to the Writing Lab for help with her papers!
  • ideal = noun meaning something or someone that embodies perfection, or an ultimate object or endeavor:
    Mickey was the ideal for tutors everywhere.
  • ideal = adjective meaning embodying an ultimate standard of excellence or perfection, or the best:
    Jennifer was an ideal student.

Its, It's

Lead, Led

  • lead = noun referring to a dense metallic element:
    The X-ray technician wore a vest lined with lead.
  • led = past-tense and past-participle form of the verb to lead, meaning to guide or direct:
    The evidence led the jury to reach a unanimous decision.

Than, Then

Than used in comparison statements: He is richer than I.
used in statements of preference: I would rather dance than eat.
used to suggest quantities beyond a specified amount: Read more than the first paragraph.
Then a time other than now: He was younger then. She will start her new job then.
next in time, space, or order: First we must study; then we can play.
suggesting a logical conclusion: If you've studied hard, then the exam should be no problem.

Their, There, They're

To, Too, Two

  • To = preposition, or first part of the infinitive form of a verb:
    They went to the lake to swim.
  • Too = very, also:
    I was too tired to continue. I was hungry, too.
  • Two = the number 2:
    Two students scored below passing on the exam.

Two, twelve, and between are all words related to the number 2, and all contain the letters tw.

Too can mean also or can be an intensifier, and you might say that it contains an extra o ("one too many")

We're, Where, Were

Your, You're

I/E Rule

Write I before E

Except after C

Or when it sounds like an A

As in "neighbor" and "weigh"

i before e: relief, believe, niece, chief, sieve, frieze, field, yield

e before i: receive, deceive, ceiling, conceit, vein, sleigh, freight, eight


seize, either, weird, height, foreign, leisure, conscience, counterfeit, forfeit, neither, science, species, sufficient

Please see our exercises to practice these rules.

-ible, -able Rule

-ible -able
If the root is not a complete word, add -ible.

aud + ible = audible

  • visible
  • horrible
  • terrible
  • possible
  • edible
  • eligible
  • incredible
  • permissible
If the root is a complete word, add -able.

accept + able = acceptable

  • fashionable
  • laughable
  • suitable
  • dependable
  • comfortable

If the root is a complete word ending in -e, drop the final -e and add -able.

excuse - e+ able = excusable

  • advisable
  • desirable
  • valuable
  • debatable

Some exceptions:

  • contemptible
  • digestible
  • flexible
  • responsible
  • irritable
  • inevitable

Try some exercises for spelling -ible and -able correctly.

Please note we are in the process of revising our exercises. They will eventually be altered to reflect those revisions.