Grammar girl here, today's topic is a positive.

Guest writer Bonnie Tranger writes,

Today we have to decide if information is essential or extra, because if it's extra we'll

need some extra commas.

The concept I'm referring to is called an a positive.

A listener, Mary, raised this topic when she asked, is it okay to start a sentence

with a vocational counselor, comma, Jane Smith, comma, has agreed to help me get a job?

Is this okay or should it be vocational counselor, comma, Jane Smith, comma, has agreed to help

me get a job?

Well Mary, yes in one case, but no in another.

Before we get into the details of this fairly complicated topic, we need to find out what

an a positive is.

It's a noun or a noun phrase that's placed next to another noun or noun phrase to help

identify it.

So at the beginning of this episode I said a listener, comma, Mary, comma, raised this topic.

In this sentence, the subject is a listener.

The name Mary is an a positive.

Oppositives can be essential information or extra information.

Only a positive that are extra information get commas.

The question now is whether the name Mary is essential or extra.

The rule for a positive is that if the information is essential, you don't use commas.

If it's extra, you use extra commas.

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