JUSTIN: What are you playing at?

RON: You're a Parselmouth! Why didn't you tell us?

HARRY¹: I'm a what?

HERMIONE: You can talk to snakes.

HARRY: I know. I mean, I accidentally set a python on my cousin Dudley at the zoo once... once! But so what? I bet loads of people here can do it.

HERMIONE: No. They can't. It's not a very common gift, Harry. This is bad.

HARRY: What's bad? If I hadn't told that snake not to attack Justin -

RON: Oh, that's what you said to it.

HARRY: You were there! You heard me!

RON: I heard you speaking Parseltongue. Snake language.

HARRY: I spoke² a different language? But I didn't realize -- how can I speak a language without knowing I can?

HERMIONE: I don't know, Harry. But it sounded like you were egging the snake on or something. Harry, listen to me. There's a reason the symbol of Slytherin House is a serpent. Salazar Slytherin was a Parselmouth. He could talk to snakes, too.

RON: Exactly. And now the whole school's gonna to think you're his great-great-great grandson or something.

HARRY: But I'm not. I can't be.

HERMIONE: He lived a thousand years ago. For all we know... you could be.

妙语佳句，活学活用

1. Play at

Play at 在这里的意思是"做，参加，从事于"， What are you playing at? 的意思就是"你在耍什么把戏？"此外，play at 还有以下一些常用意义：
1) 玩，做游戏，假扮……玩，例如：The children are playing at hide-and-seek. The children are playing at policemen and robbers.
2) 打球，打牌，例如：Can we play at cards this evening?
3) 儿戏似地做，不认真地干，例如：She was just playing at keeping house, letting the others do all the work.

2. Set on

这个片语也写做set upon，意思是"to attack or cause to attack someone physically³ or emotionally"，例如：The man sets his dog on a stranger.

3. Loads of

Loads of 表示"许多的，大量的"，也可以用 a load of 来表示同样的意思，例如：loads of parties during the holiday season，To the reader's disappointment, the leading article in this issue of the magazine is a load of rubbish.

4. Egg on

"怂恿，煽动某人做某事"的意思，例如：Jack is always egging me on to drive faster.