1.nobody“没有人”作主语时,谓语动词用单数.
There wsa onbody in the room.
另外：它还有“小人物,无足轻重的人”的意思
Don't makefriends with a nobody like him.
2.no one 用于指人,不与of 连用.用作单数
No one told us about that.
3.none 既可以指人也可以指物,可以与of 连用.用作单数或复数.
-How many elephants did you see?-None
None of them have (has)arrived.