Most of you who know me know that incorrect grammar usage and misspelled words, especially in formal writing, or on a web site, are bugaboos for me. And my mind will quickly discredit any information I read there or find on the web that contains such things, no matter how otherwise well-qualified the author might be. It’s my belief that if you care about your audience and about your writing, you’ll take steps to ensure that it’s correct in every aspect. Nothing destroys credibility faster than misspelled or incorrectly used words.

So here is my quick and dirty run-down of the top ten most common grammatical errors, misused words and misspelled words to help you on your way to better cred.

1. Could Of/Could Have?

Could of does not exist. Neither do should of, will of, or would of as verbs. Write could have, should have, will have, or would have. If you want to emphasize the pronunciation, write it as a verb contraction: could’ve, should’ve, will’ve, or would’ve.

2. Certain Adverbs Ending in -S

The adverbs anyway, anywhere, everywhere, nowhere, and somewhere do not end with an -s.

Incorrect:
I put the pen somewheres around here.

Correct:
I put the pen somewhere around here.

3. Between/Among

Between is with two people or things. Note the combination two in a number of words meaning “two” such as two, twice, and twin. Among is used when discussing three or more people or things.

Examples:
She had to choose between licorice and cherry.
She had to choose among licorice, cherry, and lime.

Between is used with and. From is used with to. Never use to with between.

Incorrect:
We shuttled between New York to Chicago.

Correct:
We shuttled between New York and Chicago.
We shuttled from New York to Chicago.

4. Accept/Except

If you offer me Godiva chocolates I will gladly accept them—except for the candied violet ones. Just remember that the “X” in “except” excludes things—they tend to stand out, be different. In contrast, just look at those two cozy “C’s” snuggling up together. Very accepting. And be careful; when typing “except” it often comes out “expect.”

5. Affect/Effect

This one can be tricky and it depends on the context. Most of the time, just remember that affect is a verb and effect is a noun. Grammar Girl has a great mnemonic to help you remember, and she goes into much greater detail about the subtleties of these two words.

The problems and confusion can come about when one or the other of these words is used differently. For example, affect as a noun, which is a psychology term meaning the mood that someone appears to have. “She displayed a happy affect.” Or when you are using effect as a verb. In this case, effect means to bring about change. “The newly-passed ordinance was designed to effect change across a broad spectrum of traffic laws.” For this particular pairing of affect/effect, just remember that the change that was effected by the new law affected a lot of people.

For more reading about this particular word pairing, check out this discussion at the University of Kansas.

6. Its/It’s

Misuse of its and it’s is appallingly prevalent and it really shouldn’t be. It’s very simple. Use its as a possessive; use it’s as a contraction of it is. If you can remember that “it’s” is a contraction of “it is” then you can also remember that any other time, it’s its! Clear as mud, huh?

Correct:
It’s a given that the dog will lick its privates only when company is present.

Incorrect:
Its not easy training a kitten to use it’s litter pan.

7. Assure/Ensure/Insure

To “assure” a person of something is to make him or her confident of it. According to Associated Press style, to “ensure” that something happens is to make certain that it does, and to “insure” is to issue an insurance policy. Other authorities, however, consider “ensure” and “insure” interchangeable. To please conservatives, make the distinction. However, it is worth noting that in older usage these spellings were not clearly distinguished.

8. Chose/Choose

This is just a matter of remembering present and past tenses. Choose is the present tense verb; chose is the past tense verb. You chose tequila last night; you choose aspirin this morning.

9. Lose/Loose

This confusion can easily be avoided if you pronounce the word intended aloud. If it has a voiced Z sound, then it’s “lose.” If it has a hissy S sound, then it’s “loose.” Here are examples of correct usage: “He tends to lose his keys.” “She lets her dog run loose.” Also, “Alcohol causes one to lose one’s inhibitions; one then becomes somewhat loose.”

10. 30 of the Top 200 Most Commonly Misspelled Words

accommodate
accomplish
arctic
auxiliary
Caribbean
correlate
defendant
dependent
ecstasy
embarrass
exaggerate
gauge
grammar
harass
hemorrhage
lieutenant
millennium
misspelled
optimism
parallel
pavilion
precede
questionnaire
recede
sacrilegious
skiing
souvenir
supersede
vacuum
withdrawal

Sources: www.englishplus.com; www.wsu.edu/~brians/errors/