2 sentences

1. 我肯定他会通情达理的。

   wǒ kěn​dìng tā huì tōng​qíng​dá​lǐ de.

   I'm sure he'll be reasonable.

   Source: OpenSubtitles

2. 他是一个通情达理的人，一定会理解你的难处。

   tā shì yī gè tōng​qíng​dá​lǐ de rén, yī​dìng huì lǐ​jiě nǐ de nán​chu.

   He is a reasonable person and will surely understand your difficulties.

   Source: Dong Chinese Dictionary