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".

Input: Consider Input: A solution presented itself yesterday.

Output: acceptable


Input: Consider Input: It tries to be warm in September.

Output: unacceptable


Input: Consider Input: He rowed Penny across the lake.


Output: acceptable