A young woman named Betty was doing some shopping one day, when she wandered into a kitchenware shop and saw a cylindrical metal object.
“What’s this?” she asks the assistant.
“It’s a Thermos flask,” the assistant replies.
“What does it do?” Betty asks, still unsure.
“It keeps hot things hot and cold things cold,” the assistant replies.
Betty thought that was quite marvellous, so she buys one and takes it to her beauty salon the next day.
“Look what I’ve got,” she tells the other ladies excitedly. “It’s a Thermos flask.”
The ladies are impressed.
“But what does it do?” they ask.
“It keeps hot things hot and cold things cold,” Betty replies.
“And what have you got in it?” they ask.
Betty beams a proud smile,
“Two cups of coffee and a chocolate ice-cream!”