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: Both rats gave a polite nod at their name.

SOLUTION: Plural

PROBLEM: " Because a woman who loves selflessly, eternally - that's his true wealth.

SOLUTION: Singular

PROBLEM: When they got inside Serena handed over her prized possession, the birthday cake.

SOLUTION:
Singular