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: I swallowed, hunger of a different sort making my fangs lengthen.

SOLUTION: Singular

PROBLEM: Had his uncle grown forgetful in his old age ?

SOLUTION: Singular

PROBLEM: A black silk square stuck out of his left chest pocket.

SOLUTION:
Singular