破旧立新
break with the outmoded and establish the new
破旧俗,立新风break with outmoded customs and establish(or build up) new ones;create sth new in place of the old
破旧立新pò jiù lì xīn
扫除一切陈旧过时的东西,把一切符合时代发展的东西建立起来。destroy the old and establish the new, eradicate the old and foster the new, abolish the old and build up the new