[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

三坟五典    三灾八难    三亲四眷    三回五解    三毛七孔