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: But immortality is such a great gift that it would only be bestowed on an individual who had something very precious to offer.'

SOLUTION: Singular

PROBLEM: The thug jerked and fell to the floor.

SOLUTION:
Singular