3 sentences

1. 他嘴上口服，心里却很不服气。

   tā zuǐ shàng kǒu​fú, xīn​li què hěn bù fú​qì.

   He says he is convinced, but in his heart, he still disagrees.

   Source: Dong Chinese Dictionary

2. 这次处罚很公平，大家都表示服气。

   zhè cì chǔ​fá hěn gōng​píng, dà​jiā dōu biǎo​shì fú​qì.

   The punishment was fair, and everyone accepted it.

   Source: Dong Chinese Dictionary

3. 他的技术确实比我高明，我打心底里服气。

   tā de jì​shù què​shí bǐ wǒ gāo​míng, wǒ dǎ xīn​dǐ lǐ fú​qì.

   His skills are indeed superior to mine; I am truly impressed from the bottom of my heart.

   Source: Dong Chinese Dictionary