2 sentences

1. 面对铁证，他感到无话可说。

   miàn​duì tiě​zhèng, tā gǎn​dào wú​huà​kě​shuō.

   In the face of ironclad evidence, he was left speechless.

   Source: Dong Chinese Dictionary

2. 他的指纹留在现场，这是他作案的铁证。

   tā de zhǐ​wén liú zài xiàn​chǎng, zhè shì tā zuò'àn de tiě​zhèng.

   His fingerprints were left at the scene, which is ironclad evidence of his crime.

   Source: Dong Chinese Dictionary