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.

The off-duty homicide investigator put her napkin on the table, not realizing the impact of her words on the latecomers.
Singular

His footsteps echoed like a death knell when he walked away.
Plural

There was another bump, and then a scrape.

Singular