不可推卸的責任 compelling obligation
不可再生資源 non-renewable resources
布雷頓森林體系 Bretton Woods System
不良貸款 non-performing loan
不買帳 not take it; not go for it
不眠之夜 white night
不明飛行物 unidentified flying object (UFO)
不拿原則換人情 refrain from seeking personal favor at the expense of principle
補缺選舉 by-election
不惹是非 Stay out of trouble.; Let sleeping dogs lie.
不速之客 gate-crasher
不惜一切代價 spare no effort; go all out; do one's best
不信任投票 vote of non-confidence
步行街 pedestrian street