前事

past events / antecedent / what has happened

front / forward / ahead / first / top (followed by a number) / future / ago / before / BC (e.g. 前293年) / former / formerly

matter / thing / item / work / affair / CL:件[jian4],樁|桩[zhuang1],回[hui2]

don't forget past events, they can guide you in future (idiom); benefit from past experience