Hi,
My son who is in 6th grade is having problems with simple subjects in sentences. Unfortunately grammar is not my strong suit so here I am. On a quiz he was given the following sentence:
There are hundreds of thousands of people at rest in the cemetery.

The question asks whether the word "There" is
A-simple subject
B-simple predicate
C-both
D-neither
He chose "D" but was marked wrong.
What is the correct answer and why? Thank you!

The subject of the sentence is:

"hundreds of thousands of people at rest in the cemetery"

The verb is:

are

The predicate is:

There

For reasons of emphasis, we order the sentence backwards, but to look at it grammatically, order it like this:

Hundreds of thousands of people at rest in the cemetery are there.

This sentence has the same structure:

Lots of people sleeping in the hall are on the mats.

In this version, the predicate is more obvious.