lǎo / shī / xiān / zài / hēi / bǎn / shàng / shì / fàn / shù / wān / gōu / de / xiě / fǎ / zài / ràng / dà / jiā / liàn / xí

老师先在黑板上示范竖弯钩的写法，再让大家练习。

The teacher first demonstrated how to write the vertical-bend hook on the board, then had everyone practice.