Fish use their swim bladder to float or sink in the water.

I achieved a big success.

They are always lovey-dovey, and I'm very envious.

They are always being affectionate.

The legend of Beelzebub has been handed down from ancient times.

Gyōbu was a part of the ancient Japanese government system.

My part-time job is a cashier.

He is suffering from a stomach disease.

He said his stomach hurts.

He needs to have surgery on his bladder.