Biden explained the advantages of the new system: "Our new phased adaptive approach to missile defense is designed to meet a growing threat, not only to the United States, but first and foremost to Europe,"

VOA: standard.2009.10.21

Peter was the first child of his father's second wife and thus a potential threat to the ambition of the relatives of the first wife.

彼得是他父亲与其第二任妻子的长子,因此对第一任妻子的亲戚们而言,彼得是他们的一个潜在威胁

耶鲁公开课 - 欧洲文明课程节选

I alluded to this a little bit in the first class about how humans have evolved to seek out energy because famine was the largest threat is one example of this.

第一节课的时候我提到了,人类是如何演化以便寻找能量,因为饥荒是最大的威胁,这是其中一例

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选