none用于指人或指物,可与of短语连用,用作单数或复数,总是用在一定范围之内,如：
1、None of that money on the table is mine.桌子上的钱都不是我的.
2、None of us are/ is afraid of difficulties.我们当中没有一个害怕困难.
注意：
1) none of短语中的none不能用no,no one,nothing ,nobody来代替,只能用none.
2) none和no one都是否定的,都只用在肯定句中,如：
None of them know me.他们都不认识我.
None of them don't know me.为错误,要说成：Each of them knows me.