医生告诉他持续的轻度抑郁可能是由心境恶劣引起的。

The doctor told him that his persistent mild depression might be caused by ___dysthymia.

她的心境恶劣让她即使在晴天也感到忧郁，但她仍尽力完成日常工作。

Her ___dysthymia made her feel gloomy even on sunny days, but she still managed to complete her daily tasks.