the film you saw last night was made __ on a true story that happened many years ago.
问题描述：
the film you saw last night was made __ on a true story that happened many years ago.
a. to be based b. based
答案选B,我觉得A也是可以理解的,make 的被动要还原to, 请大师指教!谢谢!
答
based on sth.以...为基础
make a film 制作电影
make a film based on sth.
明白了?