A boy sits on his father's shoulders to look at strawberries at the 7th International Strawberry Symposium on February 18, 2012 in Beijing, China. (Photo by Lintao Zhang/Getty Images)

A police officer jump ropes with a police dog at a police dog training base on July 11, 2011 in Beijing, China. The Police Dog Training Base was opened to a media visit to show the dogs skills to the public. (Photo by ChinaFotoPress/Getty Images)

5-year-old Chinese girl Wang Anna prepares meals for her grandmother and great-grandmother at home in Zhuyuan village, Guizhou province, China on March 3, 2017. Chinese girl called Wang Anna, 5, takes care of her ill grandmother and 92-year-old great-grandmother on her own every day in a mountainous village in Zhima town, Zunyi city, southwest China's Guizhou province. Her father went to jail before she was born and her mother remarried after gave birth to her. Although she is just five years old, she started to shoulder the responsibility to look after ill grandmother and elderly great-grandmother. (Photo by Imaginechina/Rex Features/Shutterstock)

This picture taken on September 3, 2014 shows a man taking pictures of floodwater released from the Three Gorges Dam, a gigantic hydropower project on the Yangtze river, in Yichang, central China's Hubei province, after heavy downpours in the upper reaches of the dam caused the highest flood peak of the year. Eleven people died and 27 others are missing after torrential rains battered southwest China's Chongqing, a municipality in the upper reaches of the Three Gorges Dam, causing thousands of houses to collapse, state media said. (Photo by AFP Photo/Stringer)

Labourers pour molten iron into a container at a foundry in Xiangfan, Hubei province in this July 2, 2010 file photo. Iron ore is enjoying its biggest rally in years, outpacing copper and oil so far in 2016, but still weak forward prices show it may be tough to stretch the bullish outlook. Improving steel prices in top market China are helping fuel iron ore's climb as producers gear up for a seasonal uptick in demand. Yet there is no shortage of doubters who see gains in the bulk commodity as fleeting given a large glut and challenges for China's economy. (Photo by Reuters/Stringer)

People dancing to buskers performances in Sai Yeung Choi Street South in Mongkok district, Hong Kong, China, 28 July 2018. After 18 years of unregulated street performances, the street performers were forced to give up the space to vehicular traffic again. (Photo by Jerome Favre/EPA/EFE)

Makeup artist He Yuhong, also known as “Yuya”, checks herself in the mirror during a photo shoot following her transformation into the “Girl with a Pearl Earring”, the 17th century oil painting by Dutch painter Johannes Vermeer, at her house in Chongqing, China on August 14, 2018. (Photo by Thomas Suen/Reuters)

The homemade Airbus A320 jet plane made by Chinese farmer Zhu Yue is being built at an open space in Kaiyuan city, northeast China's Liaoning province on February 4, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)