10 Grammar Rules Every Teacher Should Know

Rule #8 Punctuate for Meaning
We all know that a period ends a sentence. What about the other punctuation marks: ; - -- () and : ? Here’s how they work:

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  Semicolons connect short sentences; they do it easily.
  

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  Hyphens connect easy-to-misunderstand word phrases. They also join two seg-
  ments of a typeset word that is broken up because of space.
  

• 
  If you come across a dash—and you read what it says—you learn relevant information about the main sentence.
  

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  A sentence that includes parentheses (like this) adds an idea that isn’t necessary for understanding.
  

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  Colons point to a number of things: a list of items, a response to the main sentence or other information directly responsive to the main sentence.
  

Entire books are written on the comma. In this guide, we’ll narrow things down to only 5 rules.

1. 
   Commas separate words or phrases in a series of at least 3. Two styles are acceptable for their use:
   

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  a comma before the conjunction (1, 2, and 3) and
  
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  no comma before the conjunction (1, 2 and 3).
  

Commas NEVER follow the conjunction in a series (1, 2, and, 3—WRONG!). You should choose your style and keep consistent within a text. Examples are:

Butchers, bakers and candlestick makers are funny.

Going to the beach, getting a tan, and soaking up the sea air are my goals.

2. 
   Commas are used in dates that have at least 3 elements; they also follow dates with at least 3 elements. (See a pattern here?) So:
   

I was born January 5, 1963, in a town called Hope.

I was born in January 1963 in a town called Hope.

3. 
   Commas succeed introductions and precede extensions to a sentence. As in:
   

However, it’s hard to say who’s right.

You’re lying, aren’t you?

4. 
   A commas should not separate:
   

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  a subject and its predicate
  
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  a verb and its object
  
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  a preposition and its object
  

However, you will find commas that come between these. To be correct, these must separate elements in a series or set off an entire clause. For instance:

Subject Predicate

Going to the beach, getting a tan, and soaking up the sea air are my goals.

Verb Objects of the Verb

I called two stores, a warehouse and a salon to find the shampoo I wanted.

Preposition Objects of the Preposition

She went to Michigan, Illinois, and Minnesota.

Subject Clause Predicate

The woman, a stunning blonde, walked right up to the police chief.

In general, to use commas correctly you must forget the old rule that commas go wherever you pause. Instead, use them to separate words and phrases so that the sentence makes more sense. If you follow the rules above and you’re still not sure where your commas go, decide if your sentence is too complex. It’s better to break it up than to rely on punctuation to make it clear.