2 sentences for 誠 (chéng — sincere)

1. 他为人诚愿，深受乡里敬重。

   tā wéi​rén chéng yuàn, shēn shòu xiāng​lǐ jìng​zhòng.

   He is honest and sincere, and is deeply respected by his neighbors.

   Source: Dong Chinese Dictionary

2. 对待朋友应当以诚相待，不要互相欺瞒。

   duì​dài péng​you yīng​dāng yǐ chéng xiāng​dài, bù yào hù​xiāng qī​mán.

   Friends should treat each other with sincerity and not deceive one another.

   Source: Dong Chinese Dictionary