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: Love fortified her weakness.

SOLUTION: Singular

PROBLEM: A gloriously bright triple rainbow arches across the far side of the valley.

SOLUTION:
Singular