打破沙锅问到底
Insist on getting to the bottom of the matter.

【发音】dǎ pò shā guō wèn dào dǐ

【释义】问：同“璺”谐音；指陶瓷或玉石等器皿上的裂纹或裂缝。比喻对事情寻根究底。
            In Chinese, inquiring shares the same pronunciation with “crack” which is in pottery or jade. The phrase indicates one’s perseverance on questioning and finding out the truth.

【例1】那位采访者打破沙锅问到底，不过该政府发言人丝毫没有放松警惕。
           The interviewer asked some very searching questions but the government spokesman didn't drop his guard for a second.

【例2】小明老爱问为什么，老爱打破砂锅问到底。
           Xiao Ming always asks why and he'll never be satisfied until he knows everything.