Tangyu arrived at the Linshan Middle School clinic, took out his key to unlock the door, and found to his surprise that his key could not open the door. On closer inspection, he realized that the lock had been changed. Tangyu's eyebrows knitted slightly in confusion. What was going on here? Had Doctor Yang changed it? This made Tangyu somewhat puzzled. Why would the lock be changed without any apparent reason?
If it really was Doctor Yang who changed it, why hadn't he notified Tangyu? Tangyu didn't have Doctor Yang's phone number; there were records in the clinic, but he couldn't get in.
With no phone and no home address for Doctor Yang, Tangyu began to worry about where to find Doctor Yang to get the key and ask what was going on.
