user: Mark puts his blue basketball in a wooden box and closes it. Mark doesn't know it, but this is a magical box, which changes colors of things that are left inside. After a few minutes, the basketball turns green. Mark looks at the box but cannot see what is happening inside. The magical box tells Mark that it changed the color of the basketball from blue to green. Mark believes the box.

assistant: Mark opens the box and can see that the the color of the basketball is indeed green. He is surprised and amazed at the magical transformation.