Promises, promises

After all the water was gone, spit, and spilled out of her little cup, Elizabeth asks for more water.

Elizabeth: "I want more water, please!"

Me: "Do you promise not to spill it?"

Elizabeth: "No."

Me: "I mean, will you spill it?"

Elizabeth: "I'll try not to."

Me: "Do you promise?"

Elizabeth: "I promise to try not to spill it."