...until that time when his own true Heir returned to the school.

...is used to return those who have been Petrified to their original state.

At the end of the year, the house with the most points is awarded the house cup.

To Miss Hermione Granger, for the cool use of intellect...

You see, honorable as your intentions were, you too were out of bed after hours.

- That's a boggart, that is. - Very good, Mr. Thomas.

...here's what I want you to do. Excuse me.

So could you please put them on, right away? Quickly.

Look, everyone. Weasley's got himself a Howler.

Go on, Ron. I ignored one from my gran once. It was horrible.

Your father and I are so proud.

Like so.

Dementor! Dementor!

We don't even know this Tom Riddle. He sounds like a dirty, rotten snitch.

Unless it wasn't a student.

Let me introduce my assistant...

...Professor Dumbledore has granted me permission to start this Dueling Club...

Hey! Where are you going?

A bezoar is a stone taken from the stomach of a goat and it will save you from most poisons.