she's reading the book under the tree关于介词短语

问题描述:

she's reading the book under the tree关于介词短语
这里的 under the tree 是修饰the book 还是 is 状态?
如果要表达她正在看那本在树下的书,怎么说?

怎么可能修饰 book 呢,她在树下读书,很合逻辑;她在读树下的书,不合逻辑.书应该在她的手里才对啊.她在树下,书在她手里,她不在树下怎么读树下的书?
硬要那样说也行:She is reading the book which was found under the tree.