As every parent knows, smartphones and screens can be a huge distraction for young children and teenagers.
원문출처 : https://www.cnn.com/2019/08/21/sport/tennis-smartphones-us-open-spt-intl/index.html
원문출처 : https://www.cnn.com/2019/08/21/sport/tennis-smartphones-us-open-spt-intl/index.html