Do as I say--not as I write.

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  That / who

We want to hire someone who is great at grammar, and we will buy books thatwe can use for reference. Use the word "who" when you are talking about people, and "that" when you're talking about objects.

• Me, myself and I

This one got a lot of enthusiastic complaints about people using the word "myself" in sentences like "You will have a meeting with Bob and myself." Myself is a reflexive pronoun, and it's a bit confusing, so I will turn to my favorite source, Grammar Girl, who gives a great explanation about when to use I, me or myself, and when myself can be used to add emphasis, as in "I painted it myself." But the short answer? Please, never say "You'll be meeting with Bob and myself."

• Should have / should of

I think the problem here is that the words "should have" and "could have" were contracted in spoken English to "should've" and "could've" and some people now think that means "should of" and "could of." The correct expression is "should have," "could have," or "would have" and that is how you write it out.

• Pluralizing with apostrophes

The way we make words plural in the English language is usually by adding the letter 's' to the word. So egg becomes eggs and CEO becomes CEOs. Apostrophes are not used to pluralize words. Ever.

• Less / fewer

Fewer is used when you're talking about something you can count, and less is used for things you can't specifically quantify. So if you want to weigh less, you will want to eat fewer candy bars.

• Then / than

This pair got a lot of mention in the other article's comments section. If you're confused on this one, "then" refers to the passing of time, and "than" indicates a comparison. First you need to be better than she is, and then you can win.

• Loan / lend / borrow

This one is kind of tricky. Traditionally, "lend" is a verb and "loan" is a noun. In American English, you go to the bank and ask for a loan, and they lend you money. Or they loan you money, and then you can tell people that they lent you money. Or loaned you money. And now you have a loan to pay off. I told you it was tricky. Our faithful source Grammar Girl has a tip to remember: "loan" and "noun" both have an "o" in them, and "lend" and "verb" both have an "e."

• To / too

I didn't include this because I rarely see it in cover letters, resumes or business correspondence. But apparently others see it a lot, so here you go. "To" means in the direction of, as in They went to the movies. "Too" means in addition to, as in Our daughter came along, too, or to an excessive degree, as in, We left early because it was too hot in the theater. Of course, none of these are the same as the number two.