请教一个英语语法

1. Are these your books?对

2.Is that book your father's?这是你父亲的书吗？

我们可以把这句话还原成陈述句就好理解了
那就是 That book is your father's(book).

这句话变一般疑问句。 系动词提前。就变成了
Is that book your father's

Are these your books?对

Is that your father's book ?也可以这样说
your father's放在后面的意思是your father's做book的后置定语

Is this your book?=Is this book yours?
同理Is that book your father's?
your father's在这里相当于第一句中的yours

其实最后一句也是对的,在这里,that book是一体的,your father's是名词性所有格的意思

1.如果书是复数情况，Are these your books?对！
因为陈述句是These are your books.改成一般疑问句，将are提前。便成了Are these your books?
2 陈述句是 That book is your father's. 改成一般疑问句，将is提前。便成了Is that book your father's?