一个萝卜一个坑, 一个萝卜一个坑儿

yī gè luóbo yī gè kēng, yī gè luóbo yī gè kēngr

(1) [Each has his own task, and there's nobody to spare, as one hole for one radish]∶比喻一个人有一份工作, 互相替代不了; 也比喻每人各有岗位, 各有职责, 互相配合, 缺一不可

(2) [dependable]∶比喻作风踏实, 不轻举妄动