What's this?
It's a broomstick.
What's this?
It's candy/sweets.
Are these pumpkins or Jack-o'-lanterns?
pumpkins
Jack-o'-lanterns
What's this?
It's a ghost.
Go and switch the lights off!
.....
What's TRICK or TREAT? Explain.
....
Who's this?
It's a witch.
What's this?
It's a violin.
What's this?
It's a spider web.