Stephan Mueller works with colleague in his company in Lanzhou, capital of northwest China's Gansu Province, Oct. 23, 2018. Stephan, 48, came to China to work as an expatriate from Germany in 2006, and 4 years later he had his own home in China after he married a Chinese wife. In the following years, he travelled extensively in China with his wife, made more friends and learned more about Chinese society. (Xinhua/Chen Bin)