當人梯

Simplified: 当人梯

dāngréntī ㄉㄤ ㄖㄣˊ ㄊㄧ

    • to sacrifice oneself willingly so that others can succeed

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
be a human ladder
Meaning
To willingly sacrifice oneself so that others can succeed by climbing on one's shoulders. Approving.

Sources