2 sentences

1. 这种事实是无可争辩的。

   zhè zhǒng shì​shí shì wú​kě zhēng​biàn de.

   This fact is indisputable.

   Source: Dong Chinese Dictionary

2. 面对这个复杂的问题，他感到无可奈何。

   miàn​duì zhè​ge fù​zá de wèn​tí, tā gǎn​dào wú​kě nài hé.

   Faced with this complex problem, he felt completely helpless.

   Source: Dong Chinese Dictionary