Have you ever tried to read a badly punctuated piece?  Especially one where commas were either over-used or rarely used at all? Most readers find this really aggravating because it’s hard to make sense easily out of what’s written.  Sometimes the results can be unintentionally hilarious, too, but in a way that doesn’t make you look too good.  You don’t have to fall victim to these errors if you keep some simple rules in mind.

Today we’ll start with a couple of rules and continue through several subsequent posts.  First keep two things in mind:

1.  Logic is your friend.  Read your writing out loud to make sure it says what you mean and not something else.


If you carve Bill will carry the turkey to the table.

What? Is Bill being carved?  No, he’s going to carry.  You need a comma:

If you carve, Bill will carry the turkey to the table.

When I was reading outside a bird flew by my head.

???  Were you reading outside a bird?  No, you were outside reading when a bird flew by your head.

When I was reading outside, a bird flew by my head.

2.  Don’t count on grammar checkers for much help. It’s almost impossible to program for the various uses of the comma.

Slow Sign

When to Use Commas

One of the most common uses of the comma is before a co-ordinating conjunction. Coordinating conjunctions are words like “and” or “but” that link independent clauses.  Independent clauses are groups of words that could stand alone as a sentence.

In English we have seven coordinating conjunctions: and, but, or, nor, for, so, and yet. Where a period can be likened to a “stop” sign, the comma can be likened to a “slow” sign in this application.


Pedro rushed to catch his little sister before she tumbled down the two back steps, but he was too late.

Marie could have gone to the pizza parlor, or she could have gone to the Chinese restaurant.


As with many things in the English language, we have exceptions, but this one is easy.  If the two independent clauses are short, you can omit the comma.


The ground shuddered in the quake and we were terrified. (No comma needed.)

We’ll continue our work with commas in the next few posts.  In the meantime, keep a lookout for independent clauses with coordinating conjunctions and their commas.

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