2 sentences

1. 安禄山身兼三镇节度使。

   ān Lù​shān shēn jiān sān zhèn jié​dù​shǐ.

   An Lushan concurrently served as the military governor of three border garrisons.

   Source: Dong Chinese Dictionary

2. 安禄山曾任平卢、范阳、河东三镇节度使。

   ān Lù​shān céng rèn Píng Lú, Fàn Yáng, Hé Dōng sān zhèn jié​dù​shǐ.

   An Lushan once served as the military governor of Pinglu, Fanyang, and Hedong.

   Source: Dong Chinese Dictionary