不可开交

bù kě kāi jiāo

extremely (busy, heated)

Character by character

不bù
not

可kě
can

开kāi
untie

交jiāo
knot

年底大家都忙得不可开交。

At the end of the year everyone is run off their feet.

Tone: neutral.

Only after 得: 忙得/吵得/闹得不可开交.

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