
Pinyin:
bùguǎn sān qī èrshí yī
Meaning:
不顾一切;不问缘由。
casting all caution to the winds; come what may
Character breakdown and explanation:
不:not
管:mind; bother about
三:three
七:seven
二十一:twenty one
“三七二十一” is a multiplication rhyme and in this expression, it is used to indicate various conditions and results; therefore, “不管三七二十一” means to do something regardless of anything and regardless of the consequences. This expression is often followed by the specific thing that's being done.
Example sentences:
他不管三七二十一,把来闹事的人全都赶走了。
Tā bùguǎn sān qī èrshí yī, bǎ lái nàoshì de rén quán dōu gǎn zǒu le.
Regardless of the consequences, he expelled away all the trouble makers.
这事得商量着来,不能不管三七二十一,有条件没条件都做。
Zhè shì děi shāngliang zhe lái, bù néng bù guǎn sān qī èrshí yī, yǒu tiáojiàn méi tiáojiàn dōu zuò.
We need to discuss this; we cannot have a come-what-may attitude and do this in spite of anything.


