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: Heather's attempts at getting him to listen never worked.

SOLUTION: Plural

PROBLEM: Your fears are groundless.

SOLUTION: Plural

PROBLEM: The justice rose and proceeded back through the double doors.

SOLUTION:
Singular