a lot,a lot of,lots of的区别

a lot 是副词短语,修饰动词 如 I like it a lot.
a lot of =lots of用来修饰名词 如 I have a lot of books.

给你举个例子吧
1.I like her a lot.（非常，很）
我很喜欢她
2.I have a lot of books/I have lots of books.（意思一样，可以互换，大量的，很多的）

a lot 表示很多....

a lot of=lots of....

意思是一样的...

a lot of=lots of