Answer:
1. After a Quidditch match against Hufflepuff, Harry Potter secretly followed Severus Snape to the outskirts of the forest, where he overheard a furtive conversation about the Philosopher's Stone, in which Snape asked Professor Quirrell if he had found a way past the three-headed dog, and threatened him further.
2. Leg-Locker Curse
The Leg-Locker Curse (Locomotor Mortis), also known as the Leg Locking Spell was a curse that bound the legs of the victim together.
3. Harry convinces Hermione and Ron that they need to grab the stone that night. If Snape gets ahold of the Stone, Voldemort's coming back!
Step-by-step explanation:
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