Sea lions give a performance using volleyball  at Baotou Ocean World in Baotou, Inner Mongolia autonomous region on Aug 17, 2017. Since it’s currently the summer holidays, parents and children have flocked to the largest aquarium in Baotou to explore a marine world. In recent weeks, Baotou Ocean World has upgraded its facilities and services to entice more families come and join in the fun. [Photo/nmgnews.com.cn]