20. Tā shì lǎoshī ma? 他是老师吗?

B. Bú shì, tā shì xuésheng, tā jīnnián èrshíyī suì. 不是, 他是学生, 他今年21岁。 Translation: Question: Is he a teacher? Answer: No, he is a student. He is 21 years old this year.