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. China is the most important single player in this game. 在这场游戏中，中国是最重要的单打选手。
2. Most nations derive from a single tribe or a single race. 大多数国家起源于单一的部落或单一的种族。
3. Well, it said it liked our style, and we recorded our first single. 它说它喜欢我们的风格，我们录制了自己的第一张单曲。
英英解释
n.
1. a base hit on which the batter stops safely at first base
2. the smallest whole number or a numeral representing this number v.
1. hit a single
2. being or characteristic of a single thing or person
3. used of flowers having usually only one row or whorl of petals
4. existing alone or consisting of one entity or part or aspect or individual
5. not married or related to the unmarried state
6. characteristic of or meant for a single person or thing
7. having uniform application
8. not divided among or brought to bear on more than one object or objective
