When To Use Comma before a Conjunction

Writers often ask whether they should put a comma before a conjunction (e.g., "and," "or," "but"). Use a comma before a conjunction that combines two sentences into one.

Also, use a comma before the conjunction in a list of three or more items. Let's see.

What is the comma?

A comma is a punctuation mark used to mark a section in a sentence, such as separating words, phrases, a sentence, or a sequence.

Commas are often accompanied by a conjunction, a word that connects phrases or sentences (and, because, but, and however) or any other words or expressions that provide a similar function.

What is the conjunction?

A conjunction is a word that is used to connect words, phrases, and sentences. There are many conjunctions in the English language, but some common terms include:

• and
• or
• but
• because
• if
• when.

 

Cases of using a comma before a conjunction

 

The trick is knowing how to properly use spacers and couplings together. Here are the uses:

See: 17 ways to motivate yourself to learn English

1- When the sentence begins with a conjunction, we put a comma between the two sentences. Examples:

• If you need help, call me.
• Though he is rich, he is not happy.
• When I was in school, I loved math

If the two sentences are reversed and the conjunctions are placed in the middle, we will not put the comma. Examples:

• Call me if you need help.
• He is not happy though he is very rich.
• I loved math when I was in school.

 

2. In some cases, depending on style and preference, the writer may omit the comma from a sentence with two shorter independent clauses that have been joined by a conjunction:

• I’d rather walk but Jenna wants us to drive.
• Tim ate pizza and Jon had fries.

In such sentences, the inclusion or omission of the comma is often a matter of desirable effect rather than strict grammar. The writer may choose to keep the comma to create a pause:

• I’d rather walk, but Jenna wants us to drive.
• Tim ate pizza, and Jon had fries. 

 

3. If there are just two list items, don't use a comma before the conjunction. For example:

• I like burger and fries.

Use a comma before a conjunction in a list of three or more items. Example:

A: I like burger, fries, and greens. 

• There are 2 commas before "and". It called a "serial comma" or an Oxford Comma. Usually in American English.

B: I like burger, fries and greens.

• There is 1 comma. Most Brits do not use a serial comma. 

 

See: Compound Sentence: Definition, Coordinating Conjunctions and Semicolon

 

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References

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