温故知新

温故(而)知新 [wēn gù zhī xīn]

1. ■ review what has been learned and learn sth. new; gain new insights through restudying old material; learn the new by restudying the old; Reviewing the past helps one to understand the present.; review the old and learn the new; Review the past and you'll know better the present.; Review what you have learned and know what is new.; Review what you have learnt in order to learn sth. new.:

“温故知新， 可以为师矣。” “Those who learn the new by restudying the old may be teachers.”