Is that his backpack the lost and found case?
问题描述：
Is that his backpack the lost and found case?
”处填什么?on in at of?
答
at确定？为毛？确定。句义：在失物招领处的那个背包是他的吗？才吥是呢，用 in 吧！不对。用at。失物招领处是一个处所，不需要看作三维空间。额..我还是看看再说吧，先用in吧，等老师讲完之后再说。。=-=额，看来应该用in。是箱子，不是处啊。