I. Key Coincidence
A single American woman, Ms. Williamde, once forgot to bring her keys when she went out. When she returned home, she was locked out. Just as she was at a loss for what to do, the mailman delivered a letter from her brother. Inside the envelope was a key to her house! In the letter, her brother mentioned that during his last visit, Williamde had given him an extra key to the front door. When he returned to Washington D.C., he forgot to return it, so he had no choice but to mail it back to her.