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: The red firelight glinted in his auburn hair, and I could see he might have been attractive, even downright handsome, once.

SOLUTION: Singular

PROBLEM: A mass of recruits had already gravitated to the Whites.

SOLUTION: Singular

PROBLEM: The villagers were starting to reappear, slowly making their way out of their huts and from the forest into the clearing.

SOLUTION:
Plural