Aerial photo taken on Nov. 17, 2018 shows the construction site of a public dock for a national sailboat and sailboard base in Haikou, capital of south China's Hainan Province. (Xinhua/Yang Guanyu)

　　Aerial photo taken on Nov. 17, 2018 shows the construction site of a public dock for a national sailboat and sailboard base in Haikou, capital of south China's Hainan Province. (Xinhua/Yang Guanyu)

　　Aerial photo taken on Nov. 17, 2018 shows the construction site of a public dock for a national sailboat and sailboard base in Haikou, capital of south China's Hainan Province. (Xinhua/Yang Guanyu)

　　Aerial photo taken on Nov. 17, 2018 shows the construction site of a public dock for a national sailboat and sailboard base in Haikou, capital of south China's Hainan Province. (Xinhua/Yang Guanyu)