unflappability
在突发的火灾警报中，她表现出的镇定让所有人冷静下来。
Her ___unflappability during the sudden fire alarm calmed everyone down.
谈判桌上，他的沉着冷静令对方感到不安。
His ___unflappability at the negotiating table made his opponents uneasy.
面对记者的连环追问，这位发言人展现出了惊人的镇定。
The spokesperson showed remarkable ___unflappability when facing a barrage of questions.