For more than a three years, photographer Ren Shichen has traveled around China taking portraits of the country's left-behind children.
Each child poses in a classroom with a message for their absent parents on the blackboard behind them. Here, Gou Lingyu, 6, from Gaomiao Elementary School, Balipu County asks: "Mommy, where did you go? Mommy left home when I was six months old. Daddy cooks for me every day and works in the field and takes me to school. On the left hand side of the board is written: "Mommy, are you coming back?"
Wang Zixuan, 8, Gaomiao Elementary School, Gansu: "I miss daddy and mommy. Daddy and mommy went out to work. I haven't seen them in three years." Ren Shichen
Zhao Jinbao, 7, Matan Elementary School, Gansu. His message reads: "Dad, when are you coming back? My dad went to Baiyin to work for a year. Mom cooks and works in the field."
Zang Yixuan, 5, and his brother Zang Yaxuan, 4, at Ma Tan elementary school. Their messages read: "Mommy wants to have another boy." "My mommy wants to give me a little brother." Ren Shichen
Wang Baohua, 11, Majiawan Elementary School, Longmen County, Gansu. "My dad comes to join my mom's family. I like daddy. He always buys me good stuff. Daddy and mommy love each other. Grandpa and grandma also like dad. Happy family."
Ma Haishan, Bulengou elementary school, Gansu. "I want to be a doctor when I grow up. My dad passed away because of stomach issue in May, 2012. I miss dad very much. I want to be a doctor to treat more people in the future." Ren Shichen
Ma Jincai, 7, Bulenggou Elementary School, Gansu. "I want to be a policeman. My dad was buried in 2011 when he was digging coal."
Zhang Zhiyi, 7 years old, Longmenmajia elementary school: On the left it says: "Mommy doesn't let dad gamble." And on the right: "Dad, I beg you, stop gambling. Dad gambles a lot. Every time he'll come home after losing everything. Mum is very angry, and would fight with dad. I am very scared." Ren Shichen