Throw one's hat in the ring表示“某人决定参加竞选”，这个说法来自很早以前的一种风俗。那时，有的职业摔跤运动员经常到各地去旅行和当地的人才一比高低。如果当地有某个人决定和他比赛的话，那个人就把他的帽子往场里一扔，表示接受挑战。参考例句：People at first thought that the Governor of New York would throw his hat in the ring. But he waited and waited and announced at the last minute that he would not run for president.

人们开始都以为纽约州州长科莫会参加竞选。可是，他迟迟不作决定，直到最后一分钟才宣布他决定不参加竞选总统。