Is he a teacher? 否定回答

Is he a teacher? 否定回答 Is he your math teacher?(否定回答) He is a teacher怎样变一般疑问句否定句肯定回答否定回答? He iS a teacher.改为否定句 is your father a teacher?作否定回答 is this a teacher,s desk?怎么作否定回答? Is your father a teacher 作否定回答, maybe he is a teacher改为否定句怎么改? he is a teacher (否定句)下面都是 Your father is not a teacher,is he?怎么回答 He is a teacher. 英语否定句：IS this a teacher's desk? 否定回答是?