That's the dumbest thing I've ever heard of. I think I would have more fun chopping thistles with a butter knife.

Like a hot knife through butter.

Then the small man suddenly ran after them and said:
"I want to get my haircut. I say, do you know a little shop anywhere where they cut hair properly? I keep on having my hair cut, but it keeps on growing again."
One of the tall men looked at him with the air of a pained naturalist.

Death's got an Invisibility Cloak?" Harry interrupted again.
"So he can sneak up on people," said Ron. "Sometimes he gets bored of running at them, flapping his arms and shrieking...

Do you remember me telling you we are practicing non-verbal spells, Potter?"
"Yes," said Harry stiffly.
"Yes, sir."
"There's no need to call me "sir" Professor."
The words had escaped him before he knew what he was saying.

I don't understand German myself. I learned it at school, but forgot every word of it two years after I had left, and have felt much better ever since.