The multi-armed bandit problem is a part of probability theory, providing an algorithm for making optimal choices.

My grandfather has traveled the world when he was young.

He played his trump card at the end of the argument.

This antique clock is something I inherited from my grandfather.

He is good at deciphering new music scores.

I always play golf with my friends on weekends.

He is good at writing and writes a diary every day.

He is a good correspondent, always writing letters.

Sending packages by surface mail takes time, but it is cheap.

He made a large donation to the local library.