3 sentences

1. 这件事没有先例可循。

   zhè jiàn shì méi​yǒu xiān lì kě xún.

   There is no precedent for this matter.

   Source: Dong Chinese Dictionary

2. 我们应当遵循科学规律。

   wǒ​men yīng​dāng zūn xún kē​xué guī​lǜ.

   We should follow scientific laws.

   Source: Dong Chinese Dictionary

3. 我们不能总是循守故事，而不思进取。

   wǒ​men bù néng zǒng​shì xún shǒu gù​shì, ér bù sī jìn​qǔ.

   We shouldn't always stick to old routines and stop striving for progress.

   Source: Dong Chinese Dictionary