challenge /ˈtʃælindʒ/ I. n. ［c］挑战；艰难的任务：a challenge to competition 竞赛挑战；a letter of challenge 挑战书；give a challenge 提出挑战；accept/take a challenge 应战；a challenge cup 优胜杯；meet the challenge of …面对…的挑战 ‖II. vt. 向…挑战: I challenged him to a game of chess. 我要他跟我下一盘棋。