Editing a Notice: Which Errors Are Required Fixes and Which Are Choices

Four fixes, all sentence-level:

1. Comma splice with a conjunctive adverb. "...to the final exam, however the school supplies graph paper." → "...to the final exam; however, the school supplies graph paper." However joins two independent clauses, so it needs a semicolon before and a comma after; a comma alone cannot do that work.
2. Apostrophe. "Its important" → "It's important." It's = it is; its is possessive. The council is writing a notice, so this is the error the largest number of readers will see.
3. Comma splice. "...arrive by 8:45, the doors close promptly." → "...arrive by 8:45; the doors close promptly." Two independent clauses need a semicolon, period, or comma plus conjunction.
4. Double subject. "Ms. Danforth, who has taught mathematics for nineteen years, she recommends..." → delete "she." The subject is Ms. Danforth; the intervening clause does not license a pronoun restatement.
5. Comma splice, final sentence. "...score higher, this pattern is well documented..." → colon or semicolon: "...score higher; this pattern is well documented..."

Note that four of the five are the same underlying problem, comma splicing, which is why an editor should scan for commas before independent clauses rather than reading sentence by sentence for feel.

Keep "their." This is not an error and should not be edited as one.

Singular they has been standard English for centuries and is the default in every major style guide for exactly this situation, where the person's gender is unknown or irrelevant. "Each student must bring their own calculator" is grammatical, idiomatic, and reads naturally to students.

"His or her" is also grammatical but is bulkier and less inclusive, and it draws attention to the construction rather than the deadline. The council's real goal is that students bring calculators; either version accomplishes that, so the choice should go to readability.

The distinction the council needs: sentence-boundary errors make the text wrong, while pronoun choice makes it more or less effective. Mixing the two categories is how editing sessions lose an hour and produce a notice that reads worse but is not more correct. Fix the five mechanical items, vote once on style, and post.

Comprehension is a floor, not a ceiling, and the gap matters most in writing that has to be obeyed or trusted.

"People will understand it anyway" holds for things like the choice between their and his or her - readers process either without stopping. It does not hold for the deadline sentence. "Arrive by 8:45, the doors close promptly" is ambiguous at speed: some readers will parse the second clause as a separate instruction rather than a consequence, and a comma splice is precisely the structure that makes readers reread. On exam morning, a reread is a risk to the reader, not a nuisance to the writer.

So the standard varies with stakes and stakes vary by sentence. In a notice, the mechanics that carry obligations - times, deadlines, conditions - must be unambiguous, while mechanics that carry no information, such as pronoun form, can follow house style. "People will understand it" is also not a testable claim; the usable question is "what does a rushed reader do with this sentence?"