复合不定代词表示单数概念，作主语时谓语动词用单数形式。
例：Nothing is difficult in the world if you put your heart into it
不定代词的用法;
不指明代替任何特定名词或形容词的代词叫做不定代词.常用不定代词有：
some,any,all ,none,both,either,neither,each, every,other,another,much,
many,few,little,one等.
一、不定代词的用法
不定代词大都可以代替名词和形容词,在句中作主语、宾语、表语和定语.
1．作主语
Both of them are teachers．他们两人都是教师.
2．作宾语
I know nothing about this person．我对这个人一无所知.
3．作表语
This book is too much for a child．这本书对一个小孩来说太难了.
4．作定语
There is a little water in the glass．玻璃杯里有一些水.
