(OOC: sorry, I got just lazy and wrote prof. instead of professor.

)
Orr blushed,
"I'm sorry, Professor-- I won't do it again. Thank you for helping me." She watched the professor demonstrate the severing charm. It looked easy.
Orr picked up her wand and did a downwards slash moment pointing it at the bottle near the lid,
"Diffindo!". the bottle cut neatly. She looked up grinned at the professor,
"Thanks again, Professor Burbage."