Subject and verb agreement is a fundamental rule of grammar that affects the clarity and flow of your writing. It may seem basic, but it is essential to create polished, professional, and effective content.

Here are 24 rules to keep in mind when it comes to subject and verb agreement:

1. A singular subject takes a singular verb. (e.g., The cat chases after the mouse.)

2. A plural subject takes a plural verb. (e.g., The cats chase after the mice.)

3. A collective noun takes a singular verb when it refers to a group as a unit. (e.g., The team is playing well.)

4. A collective noun takes a plural verb when it refers to the members of a group. (e.g., The team are playing well.)

5. Indefinite pronouns, such as anyone, everyone, and somebody, take singular verbs. (e.g., Everyone is invited to the party.)

6. Compound subjects joined by and require a plural verb. (e.g., Tom and Jerry are best friends.)

7. Compound subjects joined by or require a verb that agrees with the closest subject. (e.g., Either Tom or Jerry is coming.)

8. Some nouns used as plural nouns but treated as singular, such as mathematics and economics, take singular verbs. (e.g., Mathematics is my favorite subject.)

9. Expressions of time, such as days, weeks, and years, take singular verbs. (e.g., Two years is a long time.)

10. Titles of books, films, and plays take singular verbs. (e.g., « The Lion King » is a classic.)

11. Words like some, most, many, and all used as subjects take a plural verb. (e.g., Some people are talented.)

12. Transitive verbs take an object and need to agree with the subject in number. (e.g., The cat caught the mouse.)

13. Inverted sentences, where the subject comes after the verb, require the verb to agree with the subject, not the noun before the verb. (e.g., On the bed lies a cat.)

14. Sentences starting with there or here require the verb to agree with the subject that follows the verb. (e.g., There are many cats in the alley.)

15. Words that appear between the subject and the verb do not affect subject and verb agreement. (e.g., The cat, along with the dog, is playing.)

16. Words that follow a preposition do not affect subject and verb agreement. (e.g., The book on the table is mine.)

17. Certain phrases, such as a number of, a majority of, and a percentage of, take a plural verb. (e.g., A majority of the people are happy.)

18. Words like each, every, and everyone take a singular verb. (e.g., Each person has their own opinion.)

19. Words like none, any, and some can take either a singular or plural verb, depending on the meaning of the sentence. (e.g., None of the cats are friendly vs. None of the milk is left.)

20. Titles of companies, organizations, and institutions can take either a singular or plural verb, depending on whether they are treated as a single entity or a collection of people. (e.g., Microsoft is hiring more employees vs. Microsoft are investing in new projects.)

21. The word there is not a subject, but it can indicate the existence of one or more subjects. (e.g., There are two cats in the room.)

22. The word each refers to individual items, while the word every refers to a group. (e.g., Each cat has its favorite toy vs. Every cat loves to play.)

23. The verb to be is irregular and requires special attention in subject and verb agreement. (e.g., He is a writer vs. They are writers.)

24. When in doubt, read the sentence aloud and trust your ear. If it sounds off, it probably is.

Subject and verb agreement may seem like a minor detail, but it can drastically affect the meaning and impact of your writing. By following these 24 rules, you can ensure your content is clear, correct, and effective.