情同手足

qíng tóng shǒu zú

as close as brothers

Character by character

情qíng
feeling

同tóng
like

手shǒu
hand

足zú
foot

他们俩虽然不是亲兄弟，却情同手足。

They aren't real brothers, but they're as close as brothers.

Tone: positive (praise).

手足 = siblings, a classical image.

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