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".

[EX Q]: Have in our class the kids arrived safely?
[EX A]: unacceptable

[EX Q]: Ron wanted to be wearing a tuxedo to the party, but Caspar didn't know whether to be.
[EX A]: unacceptable

[EX Q]: The famous mathematician existed a solution to the problem.
[EX A]:
unacceptable