引玉之砖

yǐn yù zhī zhuān

lit. a brick thrown to prompt others to produce a jade (idiom)

fig. a modest suggestion intended to prompt others to come forward with better ideas

引

yǐn

to draw (e.g. a bow)

玉

yù

jade

之

zhī

(possessive particle, literary equivalent of 的[de5])

砖

zhuān

brick