The disheartened instructor tried vainly to arouse their interest .
沮丧的教师试图激起他们的兴趣,但却是徒劳。
The enemy vainly attempted destroying the bridge .
敌人妄图破坏这座桥梁。
He vainly hopes to travel around the world on foot .
他梦想步行周游世界。
Vainly broken vaccine repetition inoculates with pair of human bodies harmful ?
白破疫苗重复接种对人体有害吗?
After vainly protesting against mr putin 's victory , angry middle-class russians have turned their attention to the regions , where they hope independent candidates can create political outposts beyond the kremlin 's control .