virgin 通常指未婚者，贞洁未被玷污的人，或指婚烟关系尚未完成者。
maiden 与virgin含义相近，但更着重年轻与未婚，或未曾发生过任何两性关系。
single 指尚未结婚的人，但更多指终生不结婚的人。
参考例句
1. Whether is the hospital by what judgement woman is maiden? 医院是凭什么判断女子是否为处女的?
2. Maiden, your simplicity, like the blueness of the lake, reveals your depth of truth. 少女啊，你的淳朴，如同那碧绿的湖水，展现出你的真理之深邃。
3. "Farewell, then, farewell, you good, pretty little maiden, " said the swallow; and he flew out into the sunshine. “那么再会吧，再会吧，你这善良的、可爱的姑娘！”燕子说。于是他就向太阳飞去。
英英解释
n.
1. an unmarried girl (especially a virgin)
2. (cricket) an over in which no runs are scored adj.
1. serving to set in motion
