2 sentences

1. 爵士乐的精髓在于即兴。

   jué​shì​yuè de jīng​suǐ zài​yú jí​xìng.

   The essence of jazz lies in improvisation.

   Source: Dong Chinese Dictionary

2. 他的即兴演讲赢得了阵阵掌声。

   tā de jí​xìng yǎn​jiǎng yíng​dé le zhèn​zhèn zhǎng​shēng.

   His impromptu speech won rounds of applause.

   Source: Dong Chinese Dictionary