切磋琢磨

qiē cuō zhuó mó

lit. cutting and polishing (idiom)

fig. to learn by exchanging ideas or experiences

切

qiē

to cut; to slice; to carve

磋

cuō

(old) to polish bones, horns, ivory etc into tools

琢

zhuó

to cut (gems)

磨

mó

to rub