What's the catch?
EXAMPLES
You're offering free samples? What's the catch? Nothing's really free.
You're giving away free tickets? What's the catch with that?
You're saying I won the lottery? What's the catch, tell me!
SITUATION
A friend tells you about an amazingly cheap vacation package they found online.
REACTIONS:
— That's crazy cheap! There's gotta be a catch!
— Wow, really? What's the catch with that deal ?!
— Wow, that's cheap! Must be a catch, right?
EXPLANATION
"What's the catch?" is like asking, "What's the trick?" or "What's the deal ?" It's when you're wondering if there's something sneaky or not so good hiding behind something that seems really nice. Like if someone offers you a ride to school without asking for anything in return, you might ask, "What's the catch?" It's like saying, "Is there a tricky thing I should know?" 'Cause sometimes, stuff can seem too good to be true, you know?