《孟子·告子章句上·第九节》
弈秋，是一个全国下围棋的高手，如果让弈秋教两个人下围棋，其中一人专心一志，就只听弈秋一个人讲课。
弈秋，通国之善弈者也。使弈秋诲二人弈，其一人专心致志，惟弈秋之为听。
Yiqiu is a national master of Go. If Yiqiu teaches two people to play Go, one of them is dedicated and only listens to Yiqiu's lecture.