He works extremely hard and therein lies the key to his success.

他工作极其努力，这就是他成功的关键。

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。

The insurance policy covers the building and any fixtures contained therein.

保险单为这座大楼及其中所有的设施保了险。

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。

I am humble before my ignorance and therein lies my honor and my reward.

在我的无知面前，我是谦卑的，这其中有着我的荣誉和我的报酬。