副词
1. They tried in vain to open the locked door.
他们妄图打开锁着的门。
2. We tried vainly to discover what had happened.
我们设法想要弄清楚发生了什么事，但却徒劳。
1. 徒劳地：vainglory 自负 | vainly 徒劳地 | vainness 无益
2. 枉然的/无益地/徒然/自夸地/自负的：vainglory /虚荣/ | vainly /枉然的/无益地/徒然/自夸地/自负的/ | vainness /无益/徒然/自负/
1. Tracks of your horse's hoofs will be left vainly in the snow.
adv
1. to no avail
e.g. he looked for her in vain
the city fathers tried vainly to find a solution
Synonym: in vain