she said that the book was based on 还是is base on a true stor

she said that the book was based on 意思是：她说这本书是基础.因为它是定语从句,所以可只考虑从句,在从句中 the book .这本书充当主语,并不是书中的其他东西,所以在这里based on 可以理解为基础.如从被动语态来说它主语错了,在整句的末尾其实还差一个由by引出的宾语.但在这被省略,可表达为：The+名词was besed on by the book.翻译是从左到右翻译,the+名词和the book 不需要颠倒