The International Horticultural Expo in Beijing differentiates itself by its scale: participation from 110 countries and international organizations, with tens of thousands of visitors a day. And volunteers have gained much from their seven-day stint.

Ma Lingqing, a 19-year old finance student at the Beijing Technology and Business University, signed up as a volunteer to broaden her horizons and make more friends. And that she did at the Expo.

"I'm in charge of stamping visitors' souvenir passports, guiding tourists with directions, and help translate if need be," she said.

She also learned about customs and the humanistic spirit of other countries. "For example, some of the Africans eat with their hands, not chopsticks or knives. Meanwhile, the Japanese are very dedicated and rigorous."

But Ma was most touched by the sense of unity from different cultures.

"One day, there was an mini concert at African pavilion. The Africans invited people from other pavilions to perform together. When I saw an African, an Asian, and a European with visitors singing an Chinese song called Jasmine, I was so touched. Music connects the world. I saw peace and love," she told CGTN.

Another volunteer who has reaped benefits from the Expo is Tang Jingpeng, a mechanical engineering student at the Beijing Information Science and Technology University.

"The biggest gain for me in volunteering is: I was able to experience team spirit, I learned about the benefits of green plants in our daily lives, and most importantly, how to use 'smile' to assist people," he said.

"In my own capacity, I plan to not use disposable chopsticks anymore when ordering food delivery," he added.

Tang, who was never really a plants guy, is now inspired by them as he spent days guiding visitors through the Botanic Garden.

"My favourite is the banyan tree with aerial roots, because it showcases the wisdom of plants. It is adaptive and able to survive in any environment. Plants are so tough, we humans too can be even more strong to face any difficulties."

All in, there were 20,000 volunteers who played a crucial part in ensuring tourists' inquiries are met. At any one time in a day, there are over 600 volunteers offering services at the Expo.

"I enjoy guiding visitors most. When they say thank you and smile at me from bottom of their hearts, I was really proud," Ma said. And this sentiment is echoed by many other volunteers.