3 sentences

1. 他自幼就开始学习钢琴。

   tā zì yòu jiù kāi​shǐ xué​xí gāng​qín.

   He has been learning the piano since childhood.

   Source: Dong Chinese Dictionary

2. 他年纪尚幼。

   tā nián​jì shàng yòu.

   He is still very young.

   Source: Dong Chinese Dictionary

3. 这匹幼驹展现出了成为良马的潜质。

   zhè pǐ yòu jū zhǎn​xiàn chū le chéng​wéi liáng mǎ de qián​zhì.

   This foal has shown the potential to become a fine horse.

   Source: Dong Chinese Dictionary