21.对…产生有利 / 不利的影响 exert positive / negative effects on…

　　22.利远远大于弊 the advantages far outweigh the disadvantages。

　　23.导致，引起 lead to / give rise to / contribute to / result in

　　24.复杂的社会现象 a complicated social phenomenon

　　25.责任感 / 成就感 sense of responsibility / sense of achievement

　　26. 竞争与合作精神 sense of competition and cooperation

　　27. 开阔眼界 widen one’s horizon / broaden one’s vision

　　28.学习知识和技能 acquire knowledge and skills

　　29.经济 / 心理负担 financial burden / psychological burden

　　30.考虑到诸多因素 take many factors into account / consideration