TASK DEFINITION: You're given a sentence and your task is to classify whether the sentence is acceptable or not. Any sentence which is grammatically correct, has a naturalistic text, is written by a native speaker and which minimizes superfluous content is acceptable, otherwise unacceptable. If the sentence is acceptable then write "acceptable", otherwise "unacceptable".
PROBLEM: Bob proved that this set is recursive.

SOLUTION: acceptable

PROBLEM: The umpire fell off it.

SOLUTION: acceptable

PROBLEM: The phone company billed me $10 for that phone call.

SOLUTION:
acceptable