3 sentences

1. 夜色悄然降临。

   yè​sè qiǎo​rán jiàng​lín.

   Night fell quietly.

   Source: Dong Chinese Dictionary

2. 这场政治谋划在暗中悄然进行。

   zhè cháng zhèng​zhì móu​huà zài àn​zhōng qiǎo​rán jìn​xíng.

   This political plotting is being carried out quietly in secret.

   Source: Dong Chinese Dictionary

3. 想到伤心处，她不禁悄然泪下。

   xiǎng​dào shāng​xīn chù, tā bù​jīn qiǎo​rán lèi xià.

   When she thought of the sad parts, she couldn't help but shed silent tears.

   Source: Dong Chinese Dictionary