vain
/veɪn; ven/ adj
(-er, -est)
1 having too high an opinion of one's looks, abilities, etc; conceited （对自己的才、 貌等）自视过高的; 自负的.
2 [attrib 作定语]
(esp rhet 尤作修辞) having no value or significance 无价值的; 无意义的
vain promises, triumphs, pleasures 空头的许诺、 虚无的胜利、 空欢喜.
3 [usu attrib 通常作定语]
useless or futile 无用的; 无益的; 无效的; 徒劳的
a vain attempt 劳而无功的努力
in the vain hope of persuading him 指望说服他而徒费口舌.
4 (idm 习语) in `vain
(a) with no result; uselessly 无结果地; 徒然
try in vain to sleep 怎麽也睡不著.
(b) fruitless or useless 无效果的; 无用的
All our work was in vain. 我们的工作全都白干了. take sb's name in vain => name1.