American-English Grammar Rules: A Practical Guide

Most grammar mistakes don’t come from not knowing the rules. They come from a handful of rules that are easy to misapply when you’re writing fast: a verb that drifts away from its subject, a pronoun that sounds right but isn’t, a modifier that attaches itself to the wrong noun.

This guide covers those trouble spots, one at a time, with real sentences you can compare against your own. Every section shows what to avoid, what to use instead, and why. It also flags the “rules” your teachers may have drilled into you that modern American style guides no longer enforce.

At GrammarVista.com USA, the goal is simple: clear rules you can apply in a few seconds. If you’re stuck on a specific word pair, see our tricky words guide. For commas, apostrophes, and dashes, head to the punctuation guide.

Subject-Verb Agreement

A singular subject takes a singular verb; a plural subject takes a plural verb. Simple in theory. In practice, extra words between the subject and the verb cause most errors.

Quick rule: Find the real subject, cross out everything between it and the verb, and then check the match.

Collective nouns

In American English, collective nouns like team, company, family, staff, and committee usually take a singular verb because the group acts as one unit.

• The team is practicing tonight.
• Apple has announced a new phone.
• The committee has reached a decision.

When the members are clearly acting as individuals, a plural verb can work, but most writers rephrase to avoid sounding awkward: “The committee members disagree about the budget.” British English treats collective nouns as plural far more often; see our American vs. British English guide for more differences.

Each, everyone, and other indefinite pronouns

Each, every, everyone, everybody, someone, anyone, nobody, and either (used alone) are singular.

• Each of the reports has a deadline.
• Everyone wants a raise.
• Neither of the options works for me.

None can go either way. “None of the cake is left” (a mass amount) and “None of the applicants were qualified” are both standard. Use singular if you mean “not one.”

Either/or and neither/nor

With either/or and neither/nor, the verb agrees with the subject closest to it.

• Either the manager or the interns are handling it.
• Either the interns or the manager is handling it.

If the singular-closest version sounds odd, put the plural subject last.

There is vs. there are

In sentences starting with there, the real subject comes after the verb.

“There’s” with a plural noun is common in casual speech, but in writing, match the verb to what follows. One more pair worth knowing: “A number of people are waiting” (plural), but “The number of people is growing” (singular).

Verb Tenses and Irregular Verbs

American English generally uses the simple past where British English often prefers the present perfect: “Did you eat yet?” is everyday American speech, while “Have you eaten yet?” works on both sides of the Atlantic. In writing, the main job is consistency. Don’t switch tenses mid-story unless the timeline actually changes.

“Should of,” “could of,” and “would of” are mishearings of the contractions should’ve, could’ve, and would’ve. Always write have.

Irregular verbs that trip people up

Dove is the common American past tense of dive; dived is also correct. Gotten is standard American English as a past participle of get (“She has gotten better”). The lie/lay pair gets its own deep dive in lay vs. lie.

Pronoun Case: I vs. Me, Who vs. Whom

Use subject pronouns (I, he, she, we, they) when the pronoun does the action. Use object pronouns (me, him, her, us, them) when it receives the action or follows a preposition.

Quick rule: Remove the other person. If “I went” sounds right, write “Sam and I went.” If “for me” sounds right, write “for Sam and me.”

“Between you and I” sounds formal, which is why people overcorrect into it, but every preposition (between, for, with, to, from) takes the object form.

Comparisons with than and as

“She’s taller than I (am)” is the traditional formal choice. “She’s taller than me” is standard in conversation. If you’re unsure, finish the sentence in your head and add the verb.

For the classic who and whom puzzle, use the he/him test: if him fits, use whom. Our full breakdown is in who vs. whom.

Pronoun-Antecedent Agreement and Singular They

A pronoun should match the noun it refers to (its antecedent) in number and should point clearly to one noun.

Remember that a company is an it in American English, even though “they” is common in speech.

Singular they is correct

Using they for one person whose gender is unknown, unimportant, or nonbinary is standard. Merriam-Webster recognizes this sense in its dictionary, APA style recommends it, and both the AP Stylebook and the Chicago Manual of Style accept it, with AP and Chicago noting that rewording is sometimes the smoother choice.

• Someone left their umbrella in the lobby.
• Each applicant should bring their ID.
• Riley said they are running late.

Singular they always takes a plural verb, just as singular you does: “they are,” “they were.” For formal writing where you’d rather avoid the debate, pluralize: “Applicants should bring their IDs.”

Articles: A vs. An

The choice depends on the sound that follows, not the letter.

• Use a before a consonant sound: a university, a one-time fee, a European trip, a historic win.
• Use an before a vowel sound: an hour, an honest mistake, an MBA, an FBI agent.

Quick rule: Say it out loud. “An MBA” starts with the sound “em,” so it gets an.

In American English, “a historic” and “a hotel” are standard because the h is pronounced. The same sound rule applies to abbreviations: a URL (you-are-el), an SEO audit (ess-ee-oh).

Misplaced and Dangling Modifiers

A modifier should sit right next to the word it describes. When it doesn’t, you get sentences that say something you didn’t mean.

Misplaced modifiers

Only is the most common offender. In casual speech “I only ate two cookies” is understood, but in precise writing, put only right before what it limits.

Dangling modifiers

A dangling modifier is an opening phrase with no logical subject in the main clause.

Quick rule: Whoever is doing the action in the opening phrase should be the first noun after the comma.

Sentence Fragments, Run-Ons, and Comma Splices

Fragments

A fragment is a group of words punctuated like a sentence but missing a subject, a verb, or a complete thought.

• ❌ Because the server went down.
• ✅ The launch was delayed because the server went down.
• ❌ Which is why we moved the meeting.
• ✅ The room was booked, which is why we moved the meeting.

Intentional fragments are fine in ads, dialogue, and casual writing (“Big news. Really big.”). In reports, emails to clients, and school papers, keep sentences complete.

Run-ons and comma splices

A run-on jams two independent clauses together with no punctuation. A comma splice joins them with only a comma.

• ❌ Run-on: The deadline is Friday we need the draft tomorrow.
• ❌ Comma splice: The deadline is Friday, we need the draft tomorrow.

You have four easy fixes:

Watch out for however. “It rained, however we played” is a splice. Write “It rained; however, we played.” The punctuation guide covers semicolons in more detail.

Parallel Structure

Items in a list or comparison should share the same grammatical form.

Pairs like not only/but also, either/or, and both/and need matching parts after each half. Parallel structure is especially important in résumé bullets: start every bullet with the same kind of verb (“Led,” “Built,” “Reduced”).

Grammar Myths You Can Stop Worrying About

Some rules taught in school were never real rules of English. Modern American style guides, including Chicago and AP, don’t enforce them.

Ending a sentence with a preposition

This is fine. “What are you looking for?” is natural; “For what are you looking?” is stiff. Rewriting to avoid a final preposition often makes a sentence worse. Just cut prepositions that add nothing: “Where are you at?” becomes “Where are you?”

Splitting infinitives

An infinitive is to plus a verb. Putting a word between them (“to boldly go,” “to really understand”) is acceptable and sometimes clearer. Compare “We expect our sales to more than double” with any version that avoids the split.

Starting a sentence with and, but, or because

All three are fine. “Because I said so.” is a fragment, but “Because the store closed early, we ordered online.” is a complete sentence.

Quick rule: If following an “old rule” makes your sentence clumsier, it probably isn’t a real rule.

Passive Voice: When to Use It

In active voice, the subject does the action: “The intern made a mistake.” In passive voice, the subject receives it: “A mistake was made (by the intern).”

Passive voice isn’t a grammar error. It’s a style choice, and it’s useful when:

• The doer is unknown: “My car was stolen.”
• The doer doesn’t matter: “The bridge was built in 1937.”
• The focus belongs on the receiver: “The patient was treated within minutes.”

Use active voice when you want clarity and accountability. “Mistakes were made” hides who made them; “We made mistakes” owns it. A quick test: if you can add “by zombies” after the verb and it still makes sense (“The report was approved by zombies”), the sentence is passive.

For words that get mixed up in otherwise good sentences, like affect vs. effect, check our word guides before you hit send.

Quick Checklist

• Find the true subject and make the verb agree with it.
• Treat team, company, and family as singular in American English.
• Match the verb to the closer subject with either/or and neither/nor.
• Use have, never of, after should, could, and would.
• Drop the other person to test I vs. me; it’s always “between you and me.”
• Use singular they with a plural verb when it fits.
• Choose a or an by sound, not spelling.
• Put modifiers, especially only, next to what they describe.
• Fix comma splices with a period, semicolon, or conjunction.
• Keep lists and paired ideas parallel.
• Don’t contort sentences to avoid final prepositions or split infinitives.
• Use passive voice on purpose, not by accident.