Run-On Sentences and Comma Splices: What They Are and How to Fix Them in 3 Easy Ways

Run-On Sentences and Comma Splices: What They Are and How to Fix Them in 3 Easy Ways

There are two common mistakes that instantly lower your essay score: run-on sentences and comma splices. They happen when you connect two complete sentences incorrectly.

If you write long sentences (which is great!), you MUST know how to fix them. Let’s make it crystal clear.

First: What is an Independent Clause?

An independent clause is a group of words that can be a sentence by itself. It has a subject + verb and expresses a complete idea.

• The country has abundant natural resources. ✅ (Independent clause — can stand alone)
• It adds greatly to its economy. ✅ (Independent clause — can stand alone)

If you join two independent clauses incorrectly, you get an error.

1. What is a Run-On Sentence?

A run-on happens when two independent clauses are joined with NO punctuation at all.

❌ WRONG – Run-On:
“The country has abundant natural resources it adds greatly to its economy.”

Let’s check:

• Clause 1: The country has abundant natural resources.
• Clause 2: It adds greatly to its economy.

Two complete sentences stuck together with nothing! This is illegal in English.

Unique Example:
❌ “My laptop battery died I lost all my unsaved work.”

2. What is a Comma Splice?

A comma splice is a specific type of run-on. It happens when you join two independent clauses with ONLY a comma.

❌ WRONG – Comma Splice:
“The company changed its policy, then their sales increased.”

Check:

• Clause 1: The company changed its policy.
• Clause 2: Then their sales increased.

You cannot connect two full sentences with just a comma!

Unique Example:
❌ “She is exhausted from IELTS preparation, she still practices writing every night.”

How to Fix Them: 3 Easy Methods (Works for Both!)

Good news! The fix for both mistakes is exactly the same. You have 3 options:

Method 1: Use a Period (The Easiest & Safest)

Just split them into two separate sentences. This is always correct!

✅ “The country has abundant natural resources. It adds greatly to its economy.”
✅ “My laptop battery died. I lost all my unsaved work.”
✅ “The company changed its policy. Then their sales increased.”

When to use: When the ideas are different or you want to be 100% safe. Perfect for IELTS beginners.

Method 2: Use a Comma + Conjunction (FANBOYS)

Join them with a comma + a coordinating conjunction: For, And, Nor, But, Or, Yet, So (FANBOYS).

✅ “The country has abundant natural resources, and it adds greatly to its economy.”
✅ “My laptop battery died, so I lost all my unsaved work.”
✅ “She is exhausted from IELTS preparation, but she still practices writing every night.”
✅ “The company changed its policy, and then their sales increased.”

IMPORTANT: Don’t forget the conjunction! Just a comma alone = comma splice.

Method 3: Use a Semicolon (;)

Use a semicolon ONLY if the two sentences have a very close relationship or are closely related ideas.

✅ “The country has abundant natural resources; it adds greatly to its economy.”
✅ “Learning vocabulary is essential; without it, you cannot write a good essay.”
✅ “Online classes offer flexibility; they require strong self-discipline.”

WARNING: Do NOT add “and, but, so” after a semicolon!
❌ “The country has abundant natural resources; and it adds greatly…” -> WRONG!

Quick Practice: Can You Fix Them?

Fix these run-ons and comma splices:

1. Online education is affordable it is accessible from anywhere.
2. The teacher explained the grammar rule, the students still made mistakes.
3. He wants to study abroad he needs to improve his English score.

Answers:

1. Online education is affordable. It is accessible from anywhere. / Online education is affordable, and it is accessible…
2. The teacher explained the grammar rule, but the students still made mistakes.
3. He wants to study abroad; he needs to improve his English score.

Pro Tip for Longer Sentences

Writing longer sentences is great if they are correct! Whenever you write a very long sentence, always ask:

Are there two independent clauses here? If yes, how did I connect them?

If you have Period / Comma + FANBOYS / Semicolon — you’re safe! If you have nothing or only a comma — FIX IT!

Try writing one long correct sentence in the comments and I’ll check it for you on Advanced English Lab!