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.

Q: Silk's daggers were already doing their deadly work.

A: Plural
****
Q: The challenge in his voice startled her.

A: Singular
****
Q: A reference to the heavyweight boxing contest held in Kinshasa, Zaire on 30th October 1974 between Muhammad Ali and George Foreman.

A:
Singular
****