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: Her aura, which moments before was clear and bright, was suddenly cloudy with a burst of mustard color.

SOLUTION: Singular

PROBLEM: Three hundred acres, that's a big place, lots of places to get lost.

SOLUTION: Plural

PROBLEM: The possibilities of how these devices came to match one another are both frightening and too open ended to be discussed in this report.

SOLUTION:
Plural