別開生面having sth. New
別有用心have ulterior motives
彬彬有禮refined and courteous urbane
兵不厭詐in war nothing is too deceitful
博古通今erudite and informed
不敗之地incincible position
不恥下問feel not ashamed to learn from one's subordinates
不可救藥be past praying for beyond redemption
不勞而獲reap where one has not sown
不屈不撓fortitude indefatigability perseverance persevere tenacity
不速之客crasher uninvited guest
不同凡響outstanding
不言而喻speak for itself tell its own story tell its own tale went without saying
不遺余力spare no effort spare no pains
不以為然not approve object to
不義之財filthy lucre filthy pelf the mammon of unrighteousness
不亦樂乎extremely
不遠千里go to the trouble of traveling a long distance
不約而同happen to coincide