Grammar Girl here, today we're revisiting the concept of restrictive versus non-restrictive

elements.

In past Grammar Girl episodes, I've talked about how to use the words which and that,

with restrictive and non-restrictive elements.

This time, we'll help you figure out what the concepts of restrictive and non-restrictive

have to do with participial phrases, such as making me cry and banging his nose and

when to use a comma before such phrases.

In case you're not up on the concepts of restrictive and non-restrictive clauses, here's

a quick review, so we're all on the same page.

A restrictive clause is just part of a sentence that you can't get rid of because it specifically

restricts some other part of the sentence.

You could say, the boy who threw up on Space Mountain wished he had stayed home.

Here, the who clause is restrictive.

It defines which particular boy wished he had stayed home, so you can't delete the clause

nor do you use commas around it.

You can't delete the clause so you don't use commas.

On the other hand, a non-restrictive clause is something that can be left off without

changing the meaning of the sentence.

You can think of a non-restrictive clause as simply additional information.

Which clauses are usually surrounded by or preceded by commas.

An example is the which clause in this sentence.

The town which lies 30 miles from the capital is famous for its potato festival.

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