Subject-verb agreement error after conjunction

When subjects or clauses are joined by conjunctions (and, or, nor, either...or), the verb must agree with the true grammatical subject - not with a nearby noun or a parenthetical phrase.

Below are clear rules, quick wrong/right pairs for work, school, and casual contexts, rewrite templates you can copy, and fast checks to fix sentences now.

Quick answer

Find the head subject, then apply the conjunction rule: "and" usually makes the subject plural; "or"/"nor"/"either...or" make the verb agree with the noun closest to the verb; parenthetical phrases (along with, as well as, together with) do not change the subject's number.

And → usually plural: The manager and the assistant are here.
Or / Nor / Either...or → verb matches the nearest subject: Neither the manager nor the assistants are available.
Parenthetical phrases (along with / as well as / together with) → ignore them for number: The manager, along with the assistants, is present.

Core explanation - identify the real subject

Decide which noun actually performs the action. Conjunctions join elements in different ways: "and" combines, "or"/"nor" create alternatives where proximity matters, and phrases like "along with" are parenthetical and should be ignored for agreement.

Underline the head subject before you choose the verb.
Cross out intervening phrases (along with, together with, including) when deciding number.
If two separate subjects are joined by "and", use a plural verb unless they form a single idea or refer to the same person.

Wrong: The pile of reports are on the desk.
Right: The pile of reports is on the desk.

Agreement with "and" (and important exceptions)

"And" normally produces a plural subject: two independent nouns joined by "and" act like a plural. Exceptions occur when the nouns form a single unit (bread and butter) or when both nouns refer to the same person.

Standard: singular + and + singular → plural verb.
Unit exception: when the pair names one item, treat it as singular (macaroni and cheese is delicious).
Parenthetical phrases after the subject don't change the verb: The CEO, along with several advisors, is attending.

Wrong: The coach and the captain is speaking to the team.
Right: The coach and the captain are speaking to the team.
Wrong: Peanut butter and jelly is my favorite snack when both are packed separately.
Right: Peanut butter and jelly are packed separately. (But: Peanut butter and jelly is a classic sandwich.)
Wrong: The CEO, along with several advisors, are attending the conference.
Right: The CEO, along with several advisors, is attending the conference.

Agreement with "or", "nor", "either...or" - the proximity rule

With "or", "nor", "either...or", and "neither...nor", the verb agrees with the subject nearest the verb. If that nearer subject is plural, use a plural verb; if singular, use a singular verb. If proximity creates confusion, rewrite.

If the closer noun is plural → plural verb; if singular → singular verb.
When clarity suffers, reorder the sentence or use a neutral construction.

Wrong: Either the manager or the employees is responsible for this error.
Right: Either the manager or the employees are responsible for this error.
Wrong: Neither the students nor the teacher were prepared.
Right: Neither the students nor the teacher was prepared.
Wrong: Either the cups or the mug belong in the dishwasher.
Right: Either the cups or the mug belongs in the dishwasher.

Real usage - work, school, and casual examples

Copy the right form to fix sentences quickly.

Work - Wrong: The report and the appendix needs to be submitted by noon.
Right: The report and the appendix need to be submitted by noon.
Work - Wrong: Either the client or the consultant has to sign the contract tomorrow.
Right: Either the client or the consultants have to sign the contract tomorrow.
Work - Wrong: The board, along with its advisors, are revising the policy.
Right: The board, along with its advisors, is revising the policy.
School - Wrong: Neither the professor nor the students understands the assignment.
Right: Neither the professor nor the students understand the assignment.
School - Wrong: The hypothesis and the results appears to contradict each other.
Right: The hypothesis and the results appear to contradict each other.
School - Wrong: Either the sample or the control group was wrong in size.
Right: Either the sample or the control groups were wrong in size.
Casual - Wrong: My buddy and his girlfriend is coming over later.
Right: My buddy and his girlfriend are coming over later.
Casual - Wrong: Either the pizza or the burgers is fine.
Right: Either the pizza or the burgers are fine.
Casual - Wrong: The dog, together with the kittens, are always underfoot.
Right: The dog, together with the kittens, is always underfoot.

Examples - common mistakes with quick corrections

Scan these short pairs; note which noun controls the verb each time.

Ignore interrupting phrases for agreement.
Treat two nouns as one idea when they form a unit.
When proximity causes doubt, reorder the sentence.

Wrong: The dog bark and the cats sleep on the sofa.
Right: The dog barks and the cats sleep on the sofa.
Wrong: The dog or the cats is making that noise.
Right: The dog or the cats are making that noise.
Wrong: Neither the teacher nor the students understands the problem.
Right: Neither the teacher nor the students understand the problem.
Wrong: Either the chairs or the table need fixing.
Right: Either the chairs or the table needs fixing.
Wrong: My sister and friend is visiting next week.
Right: My sister and friend are visiting next week.

Try your own sentence

Test the whole sentence, not just the phrase. Context often makes the right choice clear.

How to fix your sentence - three practical rewrite strategies

If the rules feel awkward, use one of these safe rewrites: reorder subjects, pluralize both, or use a neutral construction (passive, gerund, or split into two sentences). Each avoids common traps.

Reorder: place the noun nearest the verb so agreement is obvious.
Pluralize both: make both subjects plural if it fits the meaning.
Neutral rewrite: use passive voice, a gerund, or two sentences to remove ambiguity.

Original: Either the CEO or the interns is responsible. Fixes: Either the CEO or the interns are responsible. / The interns or the CEO are responsible. / Responsibility lies with either the CEO or the interns.
Original: The dog, along with the cats, are noisy at night. Fixes: The dog, along with the cats, is noisy at night. / The dog is noisy at night; the cats are too.
Original: Either the pizza or the sandwiches is fine. Fixes: Either the pizza or the sandwiches are fine. / Pizza or sandwiches are fine. / I'm fine with either pizza or sandwiches.

Memory tricks, quick checks, and a 3-second edit

Use a short routine: underline the subject, remove interrupters, and read the subject+verb aloud. If it still sounds wrong, rewrite.

Two quick mnemonics: "And = Add (plural)" and "Or/Nor = Opposite-nearest (verb follows the nearest noun)".

3-second edit: underline subject → remove interrupters → read subject + verb aloud.
If "either/or" confuses you, reorder so the plural noun is nearest the verb when you want a plural verb.
When in doubt, rewrite to eliminate ambiguity.

Hyphenation, commas, spacing and punctuation notes

Commas and parentheses often mark parenthetical material that should be ignored for agreement. Hyphens and spacing never change the grammatical number of a subject.

If commas set off extra information after the subject, ignore that information for agreement.
Hyphenated modifiers (well-known author) do not affect subject number.
A comma before "and" between two independent clauses separates clauses; each clause's verb follows its own subject.

Wrong: The director, as well as her team, are presenting results.
Right: The director, as well as her team, is presenting results.

Similar mistakes to watch for

Other traps include proximity errors inside phrases, collective nouns (team, committee), and indefinite pronouns (everyone, few). Apply the same approach: find the head noun and follow that construction's rule.

Proximity trap: "The key to the cabinets are missing." → head noun is key (singular) → "is missing".
Collective nouns: decide whether the group acts as a unit (singular) or as individuals (plural).
Indefinite pronouns: most are singular (everyone is), some are plural (few are).

Wrong: The key to the cabinets are missing.
Right: The key to the cabinets is missing.
Wrong: Everyone and the students were present.
Right: Everyone, including the students, was present.

FAQ

Should I say "the dog and the cat barks" or "the dog and the cat bark"?

Use "The dog and the cat bark." Two singular nouns joined by "and" form a plural subject, so the plural verb "bark" is correct.

Which verb do I use with "either the dog or the cats" - "is" or "are"?

Use "are" because with "either...or" the verb agrees with the noun closest to it (cats, plural): "Either the dog or the cats are..." If preferred, rewrite to avoid the proximity rule.

Does "along with" make the subject plural?

No. Phrases like "along with", "as well as", and "together with" are parenthetical and do not change the number of the subject. The verb agrees with the main subject: "The dog, along with the cats, is asleep."

How do I fix "Neither the manager nor the employees doesn't understand"?

Correct: "Neither the manager nor the employees understand." Better rewrite: "Neither the manager nor the employees understand the policy." Or split: "The manager doesn't understand. The employees don't either."

Will a grammar checker always catch these errors?

Many checkers catch obvious mismatches, but they can miss tricky conjunction/proximity cases or suggest awkward rewrites. Use a checker as a second opinion, then apply the simple rules above to confirm or rewrite for clarity.

Want a fast sanity check?

Underline the subject, ignore parentheticals, and read the subject + verb aloud. If that still feels uncertain, run the sentence through a grammar tool and apply one of the rewrite templates above for a clear, error-free result.