50 essential grammar rules in English writing

Whatever your stance, grammar rules keep your writing clear and professional. Most of us learned these basics in school, but they're easy to forget. This isn’t a guide saying you should absolutely live and die by the sword when it comes to grammar, but we have put 50 tips together to help you decide when it comes to one of the most personable things around: your writing. 

Grammar fundamentals

1. End sentences with periods.
2. Capitalise the first word of a sentence.
3. Questions get question marks.
4. Use exclamation points sparingly for emphasis.
5. Avoid multiple punctuation marks (No more !!! or ???).
6. Put commas between items in a list, including before "and" to avoid confusion.
7. Connect related independent clauses with semicolons.
8. Use colons to introduce lists or explanations.
9. Apostrophes show possession (Bob's car) or replace letters in contractions (don't).
10. Never use apostrophes to make something plural.

Subject-verb agreement

11. Singular subjects need singular verbs (The dog barks).
12. Plural subjects need plural verbs (The dogs bark).
13. Collective nouns can take either singular or plural verbs based on context.
14. Subjects connected by "and" take plural verbs.
15. Subjects connected by "or" take the verb that matches the closest subject.
16. Words like "everyone," "somebody," and "nobody" take singular verbs.
17. "As well as" doesn't make a subject plural—verb matches the main subject.
18. With "either/or" and "neither/nor," the verb matches the nearest subject.

Pronouns

19. Pronouns must match what they refer to in number and gender.
20. Subject pronouns: I, you, he, she, it, we, they.
21. Object pronouns: me, you, him, her, it, us, them.
22. Possessive pronouns: my, your, his, her, its, our, their.
23. People get "who," things get "that" or "which."
24. Subject = who, object = whom (though "whom" is becoming less common in casual writing).
25. It's = it is or it has; its = belongs to it.
26. Who's = who is or who has; whose = belonging to who.

Verb tenses

27. Present tense shows current action.
28. Past tense shows completed action.
29. Future tense shows upcoming action.
30. Present perfect (have/has done) connects past to present.
31. Past perfect (had done) shows what happened before something else in the past.
32. Future perfect (will have done) shows what will be completed before a future point.
33. Maintain consistent tense within paragraphs unless there's a reason to switch.

Modifiers and parallelism

34. Keep modifiers close to what they describe.
35. Avoid danglers ("Running down the street, the house came into view").
36. Use matching structures in lists (swimming, biking, running—not swimming, to bike, runs).
37. Keep bullet points grammatically consistent.
38. Compare similar items (not "my car" to "John").
39. Avoid double negatives as they can create confusion.
40. Use parallel structure in comparisons.

Commonly confused words

41. Their = possession; there = location; they're = they are.
42. Your = possession; you're = you are.
43. Affect = usually a verb; effect = usually a noun.
44. Then = time sequence; than = comparison.
45. Fewer = countable things; less = uncountable stuff.
46. Between = two things; among = three or more.
47. Further = figurative distance; farther = physical distance.
48. Lay needs an object; lie doesn't.
49. Accept = receive; except = exclude.
50. Complement = completes something; compliment = says nice things.

Grammar and professional credibility

Many professionals use grammar tools to catch mistakes before they publish. Grammarly offers real-time suggestions as you type, flagging potential errors and offering style improvements. The Hemingway Editor helps simplify complex sentences and identify passive voice. ProWritingAid provides in-depth reports on readability and style issues.

These tools aren't perfect, and they sometimes miss context or offer questionable suggestions. But they provide valuable second opinions when you don't have time for careful proofreading.

The purpose of grammar rules

Grammar provides structure that helps readers focus on your message rather than being distracted by errors. You can have some creative freedom with them depending on the type of content you’re creating, but they’re here to support clear communication.As you become more comfortable with these rules, they'll become second nature, allowing you to write with both correctness and confidence.