I second:
Wow! Bill Weasley's cool
How're the cauldron bottoms coming on?
A sample of fertiliser from Norway.
Society for the Promotion of Elvish Welfare
"Hermione, you're a girl!"
Padma's nose is off center.
Snuffles is living off rats.
Try taking your egg for a bath.
Aiden Lynch gets ploughed.
Accio Firebolt!
Fraternising with the enemy
Growing gills
Are you going to finish that Bouillabaisse?
Cedric stops being handsome and starts being dead
The man with red eyes and no nose
Saved by the deus ex machina
and third:
"CONSTANT VIGILANCE!" and "POTTER STINKS."
Ahem, here are a few of my own:
Wonky faint.
Dudders have a four-feet long tongue.
Hasan Mostafa waxes his moustache

.
Cedric's head is on fire.
Fred and George have white beards.
The Fourth Triwizard Champion.
She's a Veela!
Hagrid has eau-de-cologne.