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: When my tender skin has toughened enough to withstand the pressure of sheets, more visitors arrive.

SOLUTION: Plural

PROBLEM: The wraith continued straight toward her holding out the silhouette of a fork in one hand.

SOLUTION: Singular

PROBLEM: The slow revealing of her expanse of skin nearly caused an explosion in his gut.

SOLUTION:
Singular