re: he/she or they?

I know that I must use "he/she" when I don't know if the person is male or female. But I've heard people use "they" when they just mean one person and they don't know if the person is male or female. What is correct?

[Casiopea]

Originally Posted by lovelondon

I know that I must use "he/she" when I don't know if the person is male or female. But I've heard people use "they" when they just mean one person and they don't know if the person is male or female. What is correct?

Originally Posted by Humbolt

One solution is to rewrite sentences to make the problem disappear. This often works, but the writing may suffer. Another solution is simply not to worry about it, and use the plural forms they, them, and their as we commonly do in speaking. The Dictionary of English Usage dramatically clarifies the validity of this solution. It notes that while everybody and everyone are grammatically singular, they are notionally plural. They’re singular in form, but their meaning is plural, and “their natural tendency is to take singular verbs and plural pronouns.”

Thus, “Everyone should get their shovels” is completely correct. Merriam-Webster’s scholars write that “The plural pronoun is one solution devised by native speakers of English to a grammatical problem inherent in the language--and it is by no means the worst solution.” They quote abundant examples of this usage in respected English writing going back to Chaucer and Shakespeare, and including Jonathan Swift, Charles Dickens, Oscar Wilde, Franklin Roosevelt, Winston Churchill, and The New Yorker magazine. Furthermore, “...you have a choice: you can use the plural pronouns when they seem natural and you can use the singular pronouns when they seem natural.” I even like “his or her shovel”--but only occasionally.

Most of us probably don’t mean to be sexist, so it’s unfortunate if our language sometimes steers us that way. But it’s nice to know that spoken English already often uses a language of equality that the stuffy grammarians sought to banish. As we grow more into true equality, our language will further evolve to reflect and sustain our progress--we and our words go together.
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Originally Posted by Purdue

Rewriting the sentence

a. Recast into the plural.
Example Alternative
Give each student his paper as soon as he is finished.
Give students their papers as soon as they are finished.

b. Reword to eliminate gender problems.
Example Alternative
The average student is worried about his grade.
The average student is worried about grades.

c. Replace the masculine pronoun with ONE, YOU, or (sparingly) HE OR SHE, as appropriate.
If the student was satisfied with his performance on the pretest, he took the post-test.
A student who was satisfied with her or his performance on the pretest took the post-test.

d. Alternate male and female examples and expressions. (Be careful not to confuse the reader.)
Let each student participate. Has he had a chance to talk? Could he feel left out?
Let each student participate. Has she had a chance to talk? Could he feel left out?

Indefinite Pronouns
In all but strictly formal uses, plural pronouns have become acceptable substitutes for the masculine singular.

Anyone who wants to go to the game should bring his money tomorrow. Anyone who wants to go to the game should bring their money tomorrow.

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