句型转换。(10分)
I am Jack. (改为一般疑问句)
__________ __________ Jack?
They are from Cuba. (改为否定句)
They __________ from Cuba.
Is this a bus?(改为复数)
__________ __________ __________?
I am in Class Two, Grade Seven.（对划线部分提问）
__________ __________ are you in?
My friend is twelve years old.（对划线部分提问）
__________ __________is your friend?