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: My higher functions offer splendid regulation of my aqueous economy.

SOLUTION: Plural

PROBLEM: " Your new teacher, the principal, and Mrs. Groves, from the Superintendent's office.

SOLUTION: Singular

PROBLEM: His lumpy mattress left knots in his shoulders, a feeling not uncommon to the nights spent asleep in the barn back home.

SOLUTION:
Plural