A professional glass maker firing a piece in a gigantic oven .
Painter is painting a portrait .
A professional glass maker firing a piece in a gigantic oven.
Painter is painting a portrait.
It can either be a glass make or a painter. You cannot be painting a portrait and firing a piece at the same time.
It can either be a glass make or a painter . You can not be painting a portrait and firing a piece at the same time .