1.Whose book it is?It may be Sam's.There is his name on it.
2.whose shoes they are?They are maybe Liming's.They can't be Wangjian's beacause the shoes are too large to him.
3.These photos can't be Liuming's.They are maybe Liming's because the people on the photos are his parents.
4.That man must be Tom's brother.He looks like Tom.