Question

champions aren't made in gym's
( change the voice)

Answer 1

Champions are not made in gyms is passive voice.

This can be told via the fact that champions are the object on which the work is being done and that is in the front.

And third form of verb with are is being used.

To make it active voice one can say Gyms do not make champions.

Here 1st form of verb is being deployed.

Answer 2

Hi,

Here is your answer,

Champions are not made in gyms is passive voice.

Hope it helps you !