subject matter

1. N-UNCOUNT The subject matter of something such as a book, lecture, movie, or painting is the thing that is being written about, discussed, or shown. (著作、講話、電影或繪畫的) 主題

Then, attitudes changed and artists were given greater freedom in their choice of subject matter. 然後，態度轉變了，藝術家們在主題的選擇上被給予了更大的自由。