陈陈相因

chén chén xiāng yīn

(idiom) to slavishly follow old patterns; to stick to outdated conventions

陈

chén

(bound form) to lay out; to exhibit; to display

陈

chén

(bound form) to lay out; to exhibit; to display

相

xiāng

each other

因

yīn

old variant of 因[yin1]