3 sentences

1. 他表现得毫无悔改之意。

   tā biǎo​xiàn de háo wú huǐ​gǎi zhī yì.

   He showed no sign of remorse.

   Source: Dong Chinese Dictionary

2. 他已经意识到自己的错误，并决定彻底悔改。

   tā yǐ​jīng yì​shí dào zì​jǐ de cuò​wù, bìng jué​dìng chè​dǐ huǐ​gǎi.

   He has realized his mistake and decided to repent completely.

   Source: Dong Chinese Dictionary

3. 他表现出了真诚的悔改，最终得到了大家的宽恕。

   tā biǎo​xiàn chū le zhēn​chéng de huǐ​gǎi, zuì​zhōng dé​dào le dà​jiā de kuān​shù.

   He showed sincere repentance and was eventually forgiven by everyone.

   Source: Dong Chinese Dictionary