As comprehensive review of the 2022 Winter Olympics starts on how Beijing compares with other Games in terms of sporting achievements, TV ratings and economic benefits, there is one vital indication of the success of the past few weeks: the smiles athletes could not keep from their faces when they heaped praises on the ubiquitous volunteers.

"All the volunteers are so sweet and so kind. They are just so happy that we are here. We feel so welcomed. That was just insane," beamed 18-year-old American snowboarder Tessa Maud, who competed in the women's halfpipe event.

Volunteers have been integral to the success of the Olympics. According to organizers, over 18,000 volunteers, who were hand-picked from more than one million applicants, have given up their time to perform a wide variety of roles in Beijing 2022 – whether offering translation service, helping out on the venues, or working in the medical support team.

Though all volunteers (of which 94 percent are under the age of 35) had to stay inside the closed loop throughout the whole process due to the COVID-19 pandemic, and many of them had spent the Spring Festival away from their family for the very first time, the sense of pride was palpable among them.

"The whole world is fighting against the pandemic, but because of the Olympic Winter Games, we gathered together and united together," said Wei Yining, a postgraduate student from Beijing Forestry University.

"We all love volunteering and we love the Olympic Games, so we became the volunteers here. I hope the warmth from all the volunteers here can stay with you all the time. And together with this unforgettable experience, we can head toward the future," she added.

Teng Shengping, director-general of the volunteer department of the Beijing organizing committee, revealed that they have tried their utmost to make best use of volunteers' skills and brainpower.

"The volunteers are the best-known business card from the Games despite the masks. They are the ambassadors of culture, friendship and solidarity," Teng said. "When we were recruiting volunteers, we also took into account their physical conditions and knowledge of winter sports."

"Compared to Beijing 2008, volunteers have had to work harder due to the pandemic and the distances between the venues. And all of them had received extensive training, including those for both general and specific positions," she added.

Their efforts have paid off.

International Olympic Committee (IOC) President Thomas Bach has singled out the Beijing 2022 volunteers for praise on several occasions.

"A special thanks goes to all the volunteers. You make us feel at home from the very first moment we arrived. Your smiling eyes are warming our hearts. Thank you volunteers," he said earlier their month.

Juan Antonio Samaranch Jr., Chairman of the IOC Coordination Commission for Beijing 2022, has pointed out that the volunteers have displayed admirable resilience in portraying the joy and unity of the Olympic spirit.

"They are an extraordinary group of cultured people," said Samaranch Jr. "They are dedicated, enthusiastic and they have gone beyond what you can require from people volunteering."