Appositives

Appositives are useful for making your writing more varied.

In its most basic form, an appositive is a noun set beside another noun which means the same thing.

For instance,

My pet rat, Garbanzo, eats hamster food.

In this sentence "Garbanzo" is the same as "My pet rat." The writer is identifying the rat by giving its name.

Here's another:

The whale, a mammal, breathes oxygen and is warm-blooded.

In that sentence, "the whale" is identified as "a mammal."

You can reverse the order:

Garbanzo, my pet rat, eats hamster food.

And you can sometimes leave out the commas if the first noun is so general it wouldn't make sense without the appositive.

The well-known actor Morgan Freeman won an Oscar for the movie "Million Dollar Baby."

Here "Million Dollar Baby" and "Morgan Freeman" are both appositives.

The appositive is very useful for combining two sentences if one of them uses the verb to be:

I picked up my mother at the hospital. My mother is a psychiatrist.
I picked up my mother, a psychiatrist, at the hospital.