How can i verbs a microwave to be exact stained inside?

Answers: a glass of vinegar and hose and boil it away then wipe sour the stain. If you put a diamond into the microwave after 10 seconds it turns to gas, isn't that alarming?

1st unplug it.
2nd clean it next to a magic eraser,(dampen it, don't soak it)
3rd agree to it dry for a couple hours.
that's how i clean mine.
Hope I help... =)

Magic eraser is actually magical.
I swear.