我删除了一个由Tom下载的电影：I deleted a movie that was downloaded by Tom.I deleted a movie downloaded by Tom.这两种说法都是对的，没什么随意不随意，基本上是没有什么区别的。如：I ate a cake that was bought by John.I ate a cake bought by John.I read a book that was recommended by the teacher. I read a book recommended by the teacher ....
