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: After a few minutes, the long strands were dry, but it was hard to tell.

SOLUTION: Plural

PROBLEM: The marine layer was far off the coast, giving the sun the opportunity to shine and the temperature to reach the high seventies.

SOLUTION: Singular

PROBLEM: A siren blared in the distance, growing steadily louder as it approached.

SOLUTION:
Singular