2 sentences for 服役 (fú​yì — in service)

1. 这艘核潜艇已经服役超过二十年了。

   zhè sōu hé​qián​tǐng yǐ​jīng fú​yì chāo​guò èr​shí nián le.

   This nuclear submarine has been in service for over twenty years.

   Source: Dong Chinese Dictionary

2. 这艘旧军舰在服役三十年后终于退役了。

   zhè sōu jiù jūn​jiàn zài fú​yì sān​shí nián hòu zhōng​yú tuì​yì le.

   This old warship was finally decommissioned after thirty years of service.

   Source: Dong Chinese Dictionary