2 sentences for 根源 (gēn​yuán — root cause)

1. 贪婪往往是犯罪的根源。

   tān​lán wǎng​wǎng shì fàn​zuì de gēn​yuán.

   Greed is often the root cause of crime.

   Source: Dong Chinese Dictionary

2. 你应该追究这件事的根源。

   nǐ yīng​gāi zhuī​jiū zhèi jiàn shì de gēn​yuán.

   You should investigate the root cause of this matter.

   Source: Dong Chinese Dictionary