靠谱和紧扣主题,用英文怎么说就是类似跑题的反义词.我只要最简短的一个单词，或2三个词的短语

Stick closely to the subject
set up in line with the theme (of ...)
Encircle the theme / subject (of...)
highlighting the theme / subject (of...)
revolves around the theme / subject (of...)
centre on
我给的都是简短的2、3个词的呀.把of都去了就可以了.左右是同义词可以互换的
Encircle the theme
highlighting the theme
centre on
语境允许的话吧theme,subject去掉都没问题

stick to the subject

Subject closely