Catherine runs over to me with a crumpled-up leaf in her hand.
"Yes, you hid the leaf in your hand."
"No, not in your mouth."
"No, it's not like lettuce, it's not good to eat. It's a leaf from a tree."
[signing 'leaf', running back and replacing leaf exactly where she found it]
"Good girl, taking it back where you found it."
"Yes, that's a helicopter."
"Na-na ah-pah ah-pah." [shaking head]
"Yes, you're right, it's not an airplane. It's a helicopter."
"No, I'm sorry, I can't make the helicopter fly back here."