Question

英语厉害的就速速戳进来了!一般疑问句,反问句,提问

Answer 1

isn;t David? Is David your classmate? Who is your classmate?

isn;t he? Is he twelve years old? How old is he?

don;t we? Do you often help each other? Who often hele each other?

前面否定,后面肯定.前面肯定后面有否定.