271. at the expense of在损害…情况下,以…为牺牲
270. expect…of 在…期望…
269. (be) in existence存在 come into existence 出现
268. come into existence (=begin to exist)开始存在; come into use开始使用; come into effect开始运转; come into fashion开始时新; come into action开始行动; come into power开始执政; come into sight进入视野;come into blossom开花;
267. exert oneself to do sth. 努力,使劲
266. exert…on… 对…施加…
265. in excuse of 作为…的借口
264. exclusive of (=not taking into account; without) 不包括
263. exchange…for 以…交换
262. in excess of (=more than) 超过