Xu Qing, 25, began to work as a volunteer in the expo park since its trial operation period. This instance, where he happened to work in a booth near the No 3 gate, marked his third time providing volunteer services for the expo.

Xu is from the Century College of Beijing University of Posts and Telecommunications, which sits 11 kilometers away from the park in Yanqing district.

"Volunteers from our college commute by shuttle every day. We usually get up at 5:20 am and get on the shuttle at 6 am," he said, "but I feel more proud than tired here as, through our volunteer work, we are presenting Beijing's achievements in ecological development to the world."

Though brief, the interview with him was interrupted many times by a variety of inquiries from tourists passing by, reflecting the critical need for people like Xu.

In the park, there are many such volunteers who have received training to provide route guidance, first aid service and introductions to the pavilions, and have also learned how to deal with certain emergencies.