他大部分小说都贯穿着失去这个主题。

The ___theme of loss runs through most of his novels.

我认为这本书的基本主题非常原创，作者写了很多伟大的小说。

I think that the basic ___theme of the book is very original and the author has written lots of great novels.

电影的主要主题是爱与牺牲。

The main ___theme of the movie is love and sacrifice.