3 sentences

1. 这一方印章很珍贵。

   zhè yī fāng yìn​zhāng hěn zhēn​guì.

   This seal is very precious.

   Source: Dong Chinese Dictionary

2. 他在文件的末尾盖上了公司的印章。

   tā zài wén​jiàn de mò​wěi gài​shàng le gōng​sī de yìn​zhāng.

   He stamped the company's seal at the end of the document.

   Source: Dong Chinese Dictionary

3. 他在文件的末尾盖上了自己的印章。

   tā zài wén​jiàn de mò​wěi gài​shàng le zì​jǐ de yìn​zhāng.

   He stamped his seal at the end of the document.

   Source: Dong Chinese Dictionary