Zhao Shuang stitches women's clothes with a sewing machine in a small manufacturing workshop in Shenzhen, Guangdong, on March 5, 2014.[Cai Muyuan / chinadaily.com.cn]

Zhao came to Shenzhen 10 years ago, leaving her husband and their three-year-old daughter back in Hubei. Working on a 10-hour shift, she was busy stitching clothes the whole time we were talking. Sometimes she would stop when talking about her little girl, look up, smile briefly, and again hunch back in front of her sewing machine.

Although she does not have health insurance, she makes 4,000 to 5,000 yuan per month. She prefers to work in manufacturing workshops like this one, where there's no contract and she can come and go whenever she wants. Many migrant workers like her bounce between workshops, trying to make some extra money.

"I need to make money for my daughter who I really miss", said Zhao. "I will go back to Hubei once she starts middle school and find something to do there."

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