(also in no circumstances British English)NOT DO something used to emphasize that something must definitely not happen 决不,无论如何都不
Under no circumstances are you to go out.
你绝对不可以出去。
Examples from the Corpus
under no circumstances• Tears must not be allowed to fill their eyes and under no circumstances run down their cheeks.• And under no circumstances are you allowed to vote for me.• JuvenileCourtproceedings can be reported but under no circumstances may any child involved in the proceedings be identified.• But under no circumstancescomfort the baby, or hold the baby.• That is, under no circumstances must I mention to anyone that I have turned down an invitation to return to Blighty.• Lydon was adamant that under no circumstances would he rejoin the group.• Etiquettedemanded that under no circumstances would he change his mind.• The trouble with the proposal was that under no circumstances would the United States give up its ultimateveto on the bombs.