exercise
/ˈɛk.sə.saɪz/
Any activity designed to develop or hone a skill or ability.
The teacher told us that the next exercise is to write an essay.
Activity intended to improve physical, or sometimes mental, strength and fitness.
I do crosswords for mental exercise.
A setting in action or practicing; employment in the proper mode of activity; exertion; application; use.
The law guarantees us the free exercise of our rights.
The performance of an office, ceremony, or duty.
I assisted the ailing vicar in the exercise of his parish duties.
That which gives practice; a trial; a test.