Subject-verb agreement is one of the most fundamental rules of English grammar. It refers to the fact that the subject of a sentence must agree with the verb in terms of number and tense. Without proper subject-verb agreement, sentences can become confusing or unclear, and their meaning can be easily misconstrued.

Here are 21 rules to ensure correct subject-verb agreement in your writing:

1. A singular subject takes a singular verb.

Example: The cat is sleeping on the couch.

2. A plural subject takes a plural verb.

Example: The cats are sleeping on the couch.

3. Compound subjects joined by “and” take a plural verb.

Example: The cat and the dog are sleeping on the couch.

4. Collective nouns (group, team, family) can take either a singular or plural verb depending on the context.

Example: The team is playing well. The family are discussing their vacation plans.

5. Indefinite pronouns (everyone, anyone, nobody) are singular and take a singular verb.

Example: Everyone is responsible for their own actions.

6. When a singular subject is separated from the verb by words like “along with” or “as well as,” the verb remains singular.

Example: The cat, along with the dog, is sleeping on the couch.

7. When a singular and plural subject are joined by “or” or “nor,” the verb should agree with the closest subject.

Example: Neither the cat nor the dogs are allowed on the couch.

8. “Each,” “every,” and “either” are singular and take a singular verb.

Examples: Each cat has its own personality. Every dog loves its owner. Either choice is fine.

9. “None” can be singular or plural depending on the context.

Example: None of the dogs are barking. None of the water is left.

10. Collective nouns can be treated as either singular or plural depending on the writer`s preference.

Example: The committee has decided. The committee have decided.

11. A singular noun ending in “s” or “ss” takes a singular verb.

Example: The boss runs a tight ship.

12. Nouns that appear plural but are actually singular (such as athletics, mathematics, news, and politics) take a singular verb.

Example: Politics is a dirty business.

13. Titles of books, movies, and songs take a singular verb.

Example: “The Godfather” is a classic film.

14. “There” and “here” are never subjects and do not affect subject-verb agreement.

Example: There are no more cookies. Here comes the sun.

15. Verbs that end in “s” or “es” are usually singular.

Example: He walks to work every day.

16. Verbs that end in “ie” change to “y” for plural subjects.

Example: The baby cries when it`s hungry. The babies cry when they`re hungry.

17. Compound subjects joined by “or” are singular and take a singular verb.

Example: Either the cat or the dog is sleeping on the couch.

18. “None” is always singular and takes a singular verb.

Example: None of the water is left in the bottle.

19. When a subject is separated from its verb by a phrase, the verb should agree with the subject, not the phrase.

Example: The cat, not the dog, is sleeping on the couch.

20. Words that come between the subject and verb do not affect agreement.

Example: The cat, as well as the dog, is sleeping on the couch.

21. When a verb follows a singular noun clause, the verb should be singular.

Example: The fact that he is here is surprising.

Correct subject-verb agreement can make your writing clear, concise, and easy to understand. By following these 21 rules, you can ensure that your writing maintains proper grammar and readability.