The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)

The photo is an award-winning entry of an underwater photography competition. With the theme of depicting undersea world in tropical city Sanya, South China's Hainan province, the event is joined by over 30 photographers. (Photo provided to China News Service)