(1) 努力，尝试 (use of all one's strength when one is trying hard to do sth) [U]： put a lot of～into learning to swim/into one's work 努力学游泳/努力工作; Learning a foreign language requires/needs～. 学外语要/需要付出努力。save/waste～省力/费力; It takes very little～to keep your shoes polished. 费不了多大的劲就可以使你的鞋保持光洁。〖同〗 power，force，energy，labour，struggle;

(2) 努力，奋斗 (strong attempt; struggle) [C]： make an/every～to do sth 努力/竭尽全力做某事; His～to run the mile in four minutes succeeded. 他要在四分钟之内跑一英里的努力成功了。It was an～to get up early. 早起很费劲。by joint～s 共同努力; concentrate one's～s on sth 集中精力做某事; in a common～共同努力; redouble one's～s 加倍努力; relax one's～s 放松; spare no～不遗余力;〖同〗attempt，try;

(3) (努力的)结(成)果;成就 (result of an attempt; achievement) [C]：the latest～最新成果; Your drawing is a good～. 你的画是一幅佳作。a fine literary/art～ 文学/艺术杰作;

→′effortless adj 不费力的;

【辨异】effort与application、endeavour和exertion的区别见APPLICATION。