1 potential /pəˈtenʃl/ n. 潜力;可能性 // adj. 潜在的,可能的
搭 have the potential to do sth 有做某事的潜力
the potential for (doing) sth (做)某事的可能性
achieve/fulfil/realize one's (full) potential 发挥某人的(全部)潜力
例 The disadvantage is that they will make a range of charges to potential renters.

2 senior /ˈsiːniə(r)/ adj. 中学的(招收11或13岁以上学生);级别高的;高级水平的;老年的 // n. 级别(或地位)较高者;较……年长的人;高水平运动员
搭 be senior to... 比……年长/资历深 senior high school 高级中学
例 He is ten years senior to me.
He is senior to me by ten years.
He is ten years my senior.
He is my senior by ten years.

3 challenge /ˈtʃæləndʒ/ n. & vt. 挑战;质疑
搭 face/meet/accept a challenge 面对/迎接/接受挑战
challenge sb to (do) sth 挑战某人(做)某事
例 After lunch Carey challenged me to a game of tennis.

4 opportunity /ˌɒpəˈtjuːnəti/ n. 机会,时机
搭 take/seize the opportunity to do/of doing sth 抓住做某事的机会
offer/afford an opportunity 提供机会 opportunity shop 义卖商店
miss/lose/waste an opportunity 错过/失去/浪费掉机会
have an/no opportunity for doing sth/to do sth 有/没有做某事的机会
例 It's an opportunity to make the Chinese culture better known to international students.