The upper part (file) of this combo photo taken by Pan Jiamin shows migrant workers waiting for trains to go back home at a railway station in Shenzhen, south China's Guangdong Province. The lower part of the combo photo taken by Mao Siqian on April 18, 2015 shows two foreigners at a job fair in Shenzhen. This year marks the 40th anniversary of China's reform and opening-up policy. Over the past four decades, Shenzhen has developed from a small fishing village to a metropolis. (Xinhua)