3 sentences

1. 当你镇定下来时回来。

   dāng nǐ zhèn​dìng xià lai shí huí lai.

   Come back when you have calmed down.

   Source: CCMatrix

2. 我镇定下来，说是的。

   wǒ zhèn​dìng xià lai, shuō shì​de.

   I calmed down and said yes.

   Source: CCMatrix

3. 麻醉师告诉我说，我是他所见到的最镇定的人。

   má​zuì​shī gào​sù wǒ shuō, wǒ shì tā suǒ jiàn dào de zuì zhèn​dìng de rén.

   The anesthesiologist told me I was the calmest person he'd ever seen.

   Source: UM-Corpus: Education