2 sentences for 原 (yuán — source)

1. 你应该把事情的原委告诉大家。

   nǐ yīng​gāi bǎ shì​qing de yuán wěi gào​su dà​jiā.

   You should tell everyone the whole story of what happened.

   Source: Dong Chinese Dictionary

2. 凡事若不究其本原，很难从根本上解决问题。

   fán shì ruò bù jiū qí běn yuán, hěn nán cóng gēn​běn shàng jiě​jué wèn​tí.

   If you don't look into the root cause of a matter, it's hard to solve the problem fundamentally.

   Source: Dong Chinese Dictionary