You and your other fellow classmates were getting yelled at my Umbridge because she gave us a test she never warned us about our taught us SHE kept ranting and Ranting then she said while standing infront the class

"Stand up If you think your Stupid"

After a few seconds you stand up and Umbridge was confused because you were a high student

"You think your stupid she says while everyone looks at you and umbrige is standing too"