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: Lena's posture improved as she spoke.

SOLUTION: Singular

PROBLEM: I can't float it up now, the turbulence up there must be terrific !'

SOLUTION: Singular

PROBLEM: The ramp would collapse as I drove away, and the rocks might damage the wheels or undercarriage.

SOLUTION:
Singular