therein

1. ADV Therein means contained in the place that has been mentioned. 在那里[文学性] [n ADV]

By burning tree branches, pine needles, and pine cones, many not only warm their houses but improve the smell therein. 通过燃烧树枝、松针和松果，许多人不仅给屋子供暖，而且还改善里面的气味。

2. ADV Therein means relating to something that has just been mentioned. 在其中 (指与刚提及的事物相关)[正式] [n ADV]

Afternoon groups relate to the specific addictions and problems therein. 下午各小组谈到具体的成瘾病例和其中的问题。