He was ready to lend me any of the book I wanted them.为什么去掉t

这一句可以分成这两句话：
1.He was ready to lend me any of the book.
2.I wanted the books.
这两句话可以用which引导的定语从句来连接,即：
He was ready to lend my any of the book which I wanted.
这里的定语从句的which已经代替了the books作为宾语
而这个定语从句的which作为宾语,就可以省略,即：
He was ready to lend my any of the book (which)I wanted.
把which去掉,形式不变,即：
He was ready to lend my any of the book I wanted.
PS:我打了好久啊,累死了,房主要采纳我啊!

i wanted 是一个前面是省略了which的定语从句，因为which已经指代了book，所以them是多余的。