A week before her mother's birthday, she went shopping after a quick and simple lunch. When she had been looking for half an hour, she found a shop that was selling cheap umbrellas, and decided to take a black one. Her mother had lost hers the month before.

Sally was a student. It was going to be her mother's birthday. She wanted to buy her a present that would be nice and useful but not expensive.

On her way home in the train that evening she felt hungry because she had such a small lunch that she went along to the buffet car for a sandwich and a cup of coffee.

She thought, "You could carry that when you are wearing clothes of any color." So she decided to buy a lovely black umbrella and took it back to the school with her until her classes had finished.