How might a trained professional differentiate sadness related to environmental events from early signs on major depressive disorders? And how would he/she probably treat these conditions?

• 做为一个受过训练的专业人士要如何从主要抑郁症的早期症状来分辨和周遭环境事件有关的忧伤情绪？以及他/她可能如何处理这些情况？