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From Quora by C Stuart Hardwick (Award-Winning Sci-fi Author) from Houston, TX
Many people would say "Everyone should save their questions until the end", but this is widely regarded as wrong. The more correct, but convoluted form is "Everyone should save his or her questions until the end".
I can't see what's wrong with using "their" in this sentence.
As far as I know, grammar books say that you can use "their" in place of a gender-neutral collective pronoun:
- "I'm reminding everyone in class that they should do their homework at home" is perfectly fine to me and just can't imagine it being written using "his or her".