lǎo / shī / ràng / xué / shēng / bǎ / jiǔ / gōng / gé / de / měi / yī / gé / dōu / tián / shàng / shù / zì

老师让学生把九宫格的每一格都填上数字。

The teacher asked the students to fill every cell of the 3-by-3 grid with a number.