[sān tuī liù wèn]   

三    推    六    问    推：推究；问：审问。旧时指反复审训。

推：推究；问：审问。旧时指反复审讯。

Make several cross-examinations

三头两绪    三分鼎立    三阳交泰    三朋四友    三街两市