Which sentence states a fact?

 - During the summer months, volleyball is more fun to play than basketball.
 - A physical fitness teacher came up with the idea for volleyball.
The second sentence states a fact.
A physical fitness teacher came up with the idea for volleyball.
It can be proved by reading a book about volleyball.
The first sentence states an opinion.
During the summer months, volleyball is more fun to play than basketball.
More fun shows what a person believes, thinks, or feels. Another person might have a different opinion about which game is more fun.