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.

Example Input: The challenge in his voice startled her.
Example Output: Singular

Example Input: Her adrenaline was spiking again, rushing through her veins like an awakened river.
Example Output: Singular

Example Input: Skulls persisted in signaling to her to detonate the explosives strapped to Richard.
Example Output:
Plural