TASK DEFINITION: In this task you are given a sentence. You must judge whether subject of the main clause is singular or plural. Label the instances as "Singular" or "Plural" based on your judgment.
PROBLEM: There's a mumbling from the heap.

SOLUTION: Singular

PROBLEM: " Holiday romances are such a wonderful thing, until they end. "

SOLUTION: Plural

PROBLEM: The tumble of stones in the center was a large fire pit piled with wood that was ready for a flame's kiss.

SOLUTION:
Singular