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: " What's madness is that with a push of a button, they can knock us all out within seconds. "

SOLUTION: Singular

PROBLEM: The blades crashed and the room shook.

SOLUTION: Plural

PROBLEM: The wolves jumped in after them.

SOLUTION:
Plural