Some “rules” you may have heard aren’t rules of English grammar at all. Three famous ones: never split an infinitive, never end a sentence with a preposition, and never start a sentence with And or But. Like singular they, these are places where you should know the range.
| The old “rule” | What usage guides say | Example |
|---|---|---|
| Don’t split an infinitive (to + adverb + verb). | Not an error. Split it when that reads more clearly. | She decided to quickly finish her homework. |
| Don’t end a sentence with a preposition. | Not an error. Often the natural choice. | What are you looking at? |
| Don’t start a sentence with And or But. | Not an error. Good writers have done it for centuries. | But the door was locked. |
Key idea
Splitting an infinitive, ending with a preposition and starting with And or But are standard English. Some teachers and readers still object, especially in formal writing, so know your audience and choose the version that reads best.
Why it works
Many of these bans come from grammar writers of the 1600s to 1800s who measured English against Latin. In Latin an infinitive is one word, so it can’t be split; English infinitives are two words. The Chicago Manual of Style accepts split infinitives and endings with a preposition, and in 2024 Merriam-Webster reminded readers that you can end a sentence with a preposition.
Worked example: Ending with a preposition
“Who did you give it to?” or “To whom did you give it?”
- Both are grammatical.
- The second sounds more formal; the first sounds natural.
- Choose by the occasion, not by a rule.
Answer: Both are correct.
Worked example: When splitting is clearer
“We expect our club to more than double in size.”
- Try moving more than: “to double more than in size” makes no sense.
- Here the split infinitive is the clearest way to say it.
Answer: Keep the split.
Worked example: A real error, for comparison
“The list of chores are long.”
- The subject is list, which is singular.
- This breaks a real rule of standard grammar: subject–verb agreement.
Answer: The list of chores is long.
Common mistake
Treating old classroom bans as rules of grammar, and “correcting” good sentences into awkward ones (“That is something up with which I will not put”). The other mistake is assuming every reader agrees: some teachers still ask you to avoid these in formal essays. Follow the assignment, and know that the sentence is not wrong.