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: The rats do not know the warrior has arrived.

SOLUTION: Plural

PROBLEM: Bob and Jan Dove are also with us.

SOLUTION: Plural

PROBLEM: The lifeboat stood off the Seahouses harbour entrance, whilst the Belinda berthed in an empty space on the quay.

SOLUTION:
Singular