Student players take part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)

Student players take part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)

Aerial photo shows student players taking part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)

Student players take part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)

Student players take part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)

Student players take part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)

Student players take part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)

Student players take part in a training to prepare for the football match held to greet the International Children's Day at a school in Zunhua City, north China's Hebei Province, May 27, 2019. (Xinhua/Liu Mancang)