拋磚引玉（拋磚引玉|拋甎引玉）　

◎ 拋磚引玉 pāozhuān-yǐnyù

[throw out a brick to attract a jade;(fig) offer a few commonplace remarks by way of introduction so that others may come up with valuable opinions] 拋出磚去,引回玉來。比喻自謙以粗淺的見解引出別人的高見

方才婢子費了唇舌,說了許多書名,原是拋磚引玉,以為借此長長見識。——清· 李汝珍《鏡花緣》