As Silicon Valley headhunter Nick Corcidolos says, "The way you use language reveals who you are, how you think, and how you work .... You can pretend otherwise, but you can also walk around buck-naked believing you're invisible because you've got your eyes closed."

Don't walk around naked when it comes to your writing. Stay sharp, clean, and clear by avoiding common mistakes like these, which can compromise the quality of your writing as well as how you are perceived professionally:

1. Using 'that' when you should use 'who'

In writing, when you refer to a person, use "who," not "that."

Incorrect: "Héloise is the girl that is cooking tonight."

Correct: "Héloise is the girl who is cooking tonight."

This can be hard to get right because this mistake is common in conversation. Written down, it becomes more glaring.

2. Mismatching bullet points

This is particularly salient given the popularity of the listicle. When creating a list of ideas, be sure your bullets are parallel.

For example, this article lists grammar mistakes, which means each bullet should reference a mistake, not something that is correct. I would be remiss if I made the next one "Be sure to capitalize titles correctly." Since I'm listing mistakes, it should read "Capitalizing titles incorrectly."

Keep bullet points parallel to make your writing lucid.

3. Putting a comma after 'that'

When describing something, the word "which" always takes a comma, while the word "that" doesn't.

Incorrect: "She attended the concert, that was by our house."

Correct: "She attended the concert that was by our house."

Correct: "She attended the concert, which was by our house."

4. Using 'then' when you mean 'than'

This is perhaps the most common and obvious grammatical mistake on this list, and it really does make you look ignorant.

Always use "then" when referencing time (i.e., "We went to lunch, and then returned to the conference"). Never use it in comparisons -- those always take "than."

Incorrect: "The food at this year's conference is better then the last."

Correct: "The food at this year's conference is better than it was last year."

5. Not hyphenating modifiers

If you're preceding a noun with a compound adjective, you generally need a hyphen. Thus, if you're describing a quote people often cite, it's an "often-cited quote." If the adjectives do not precede the noun, you don't need the hyphen. Thus, "That quote is often cited" is also correct.

Incorrect: "She's a full blown member of the community."

Correct: "She's a full-blown member of the community."

Incorrect: "This is a well loved book."

Correct: "This is a well-loved book."

Exception: If a modifier includes an adverb that ends in "-ly," there's no need for the hyphen. Thus your "newly retired neighbor" isn't hyphenated.

6. Using 'over' when you really mean 'more than'

If you're talking about something countable, such as people, airplanes, toothbrushes, etc., use "more than." Use "over" only when referencing something not countable, such as water, dirt, gasoline, etc.

Incorrect: "Over 6 million people watched the debate."

Correct: "More than 6 million people watched the debate."

7. Using 'alot' instead of 'a lot'

This one's easy: "Alot" is not a word. Don't use it.


While it's worth investing in getting the rules of grammar right, it's also good to keep things in perspective. Even if you use a piece like this to pick up just one rule and make fewer mistakes because of it, you're trending in the right direction.

Plus, the next time you're beating yourself up for getting something wrong in your writing, remember this:

Every June, all across the United States, millions of cakes are made with the word "congratulations" on them. Roughly 60 percent get the spelling wrong.

If you grasp the irony of that, congratulations.