Lǎo / yuán / gōng / jīng / yàn / fēng / fù / shì / bù / mén / lǐ / bù / kě / tì / dài / de / tái / zhù

老员工经验丰富，是部门里不可替代的台柱。

The veteran employee is experienced and an irreplaceable pillar of the department.