1.填写谚语方知其义的上半句是什么

书读百遍，方知其义 铁不冶炼不成钢，人不运动不健康. It is the unforeseen that always happens.天有不测风云，人有旦夕祸福。

It is too late to grieve when the chance is past.坐失良机，后悔已迟。 It never rains but it pours.不鸣则已，一鸣惊人。

It takes three generations to make a gentleman.十年树木，百年树人。