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: Nora sent at the book to Peter.

SOLUTION: unacceptable

PROBLEM: People from Tucson think very highly of themselves.

SOLUTION: acceptable

PROBLEM: There appeared a ship on the horizon.

SOLUTION:
acceptable