“We’ll go and get our stuff,” said Ron in a hopeless sort of voice.
“What are you talking about, Weasley?” barked Professor Mc-Gonagall.
“Well, you’re expelling us, aren’t you?” said Ron.
Harry looked quickly at Dumbledore.
“Not today, Mr. Weasley,” said Dumbledore. “But I must impress upon both of you the seriousness of what you have done. I will be writing to both your families tonight. I must also warn you that if you do anything like this again, I will have no choice but to expel you.”
Snape looked as though Christmas had been canceled.

Harry Potter and the Chamber of Secrets - Chapter 5 : The Whomping Willow
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