Master Punctuation and Apostrophe Usage: Simple Rules with Clear Examples

Good punctuation makes writing clear, professional, and easy to read. Incorrect punctuation can confuse readers or change your meaning. Two areas cause the most problems: apostrophes and comma placement.
Let’s break both down into simple rules with examples you can use right away.

1. Apostrophe Rules

Rule 1: Show Possession

Use an apostrophe + s to show that something belongs to someone or something.

Examples:

• Sarah’s car is red. ✅ (The car belongs to Sarah.)

• The dog’s bone is missing. ✅ (The bone belongs to the dog.)

Plural nouns ending in s:

• The teachers’ lounge is on the second floor. ✅ (Lounge for several teachers.)

Rule 2: Use Apostrophes in Contractions

Contractions shorten two words into one. The apostrophe replaces missing letters.

Examples:

• don’t = do not

• you’re = you are

• it’s = it is or it has

Tip: Say the full form in your head. If it makes sense, the contraction works.

Rule 3: Never Use Apostrophes for Plurals

Do not add an apostrophe when you make a word plural.

Examples:

• Correct: I bought three apples. ✅

• Wrong: I bought three apple’s. ❌

2. Comma Placement Rules

Rule 1: After Introductory Phrases

Place a comma after words or phrases that introduce your sentence.

Examples:

• After dinner, we watched a movie. ✅

• In the morning, I will go for a run. ✅

Rule 2: In Compound Sentences

Use a comma before and, but, or, nor, for, so, yet when joining two independent clauses.

Examples:

• I wanted to go hiking, but it started raining. ✅

• She likes coffee, and he prefers tea. ✅

Rule 3: In a List of Three or More Items

Place commas between items in a series. The Oxford comma before “and” avoids confusion.

Examples:

• I bought apples, oranges, and bananas. ✅

• We invited my parents, Tom, and Sarah. ✅

Rule 4: Around Non-Essential Information

Use commas to set off extra information that is not essential to the main meaning.

Examples:

• My brother, who lives in New York, is visiting us. ✅

• The meeting, scheduled for Monday, will cover new policies. ✅

Quick Checklist for Error-Free Writing

• Ask yourself: Does the apostrophe show possession or replace missing letters? If not, leave it out.

• Use commas to guide your reader’s breathing — natural pauses often match correct comma placement.

• Always review your writing for extra or missing punctuation.

Final Word:
Mastering apostrophes and commas boosts your clarity, credibility, and professionalism. Follow these rules, practice daily, and your punctuation will feel natural every time you write.