"Though many people think the job is dull and repetitive, Zhang Yu enjoys it and tries to give a hand to others," says Zhang Hanjiang, who works at the same station with Zhang Yu.

When Zhang Yu distributes packages, he often carefully records the daily habits of the recipients. For example, he has come to know which clients have babies and need to take a longer afternoon rest, the households with only seniors, and the time that the office workers are available. He considers all of these factors when deciding when to deliver each client's packages. He also helps them out by removing trash for his elderly clients, and taking food to offices of those that work, for example.

As a result, he has won the hearts of many clients. "They always give me a big smile and sometimes even a bottle of water or some fruit when I deliver on a very hot day," Zhang Yu says. "Some have even become my friends outside of work."