From
宋·
计有功《
唐诗纪事》: the Tang monk-poet Qi Ji (
齐己) wrote a poem 《
早梅》 with the line '
前村深雪里,
数枝开' ('several branches in bloom'). Zheng Gu (
郑谷) suggested changing
数枝 ('several branches') to
一枝 ('a single branch') to fit 'early plum.' Qi Ji bowed in thanks, and Zheng was honored as his
一字师 — one-character master.