anumberof和alotof用法有什么区别

a number of意思是“许多”，相当于 many，修饰可数名词复数。作主语时，谓语动词用复数。

如：

She retained a number of copies for further annotation.

她保留了许多副本以便作进一步的注解。

This view is contrary to the aims of critical social research for a number of reasons之所以说此观点违背了批判性社会研究的宗旨，有几点理由。

A number of houses were burnt down in the fire.在火灾中，好些房子给烧毁了

a lot ofa lot of与lots of的意思和用法完全相同，都是起形容词作用的词组，可用于修饰可数或不可数名词。相当于many或much. 

如： There are a lot of / lots of famous movie stars in the USA. 美国有许多著名的电影明星。

We need a lot of [lots of] money. 我们需要很多钱。

He has quite a lot of [lots of] friends. 他有很多朋友。

A lot of people think that time is money.(许多的人认为时间就是金钱。)

修饰主语时，谓语的数取决于它所修饰名词的数。

如：

A lot of money was spent on it. 在它上面花了很多钱。

A lot of people were interested in it. 对此感兴趣的人很多。

a number of后只能接可数名词，如果在a后面再加great就变a great number of就等于many(many修饰可数名词）另外还有一个the number of，它们的区别就是，the number of后面加单数动词，举个例句，The number of students in our class is fifty(注意这个is是单数动词），a number of后面加复数动词，举个例句，A number of students in our class are from Shanghai(注意这个are是复数动词），a lot of 既可接可数又可接不可数名词，另外a lot of 就等于lots of。