a lot of可以等同于lots of或者many,意思是很多。修饰可数名词复数或不可数名词。例句:There are a lot of books in the library.
意思相同的词(组)还有:
many修饰可数名词
much修饰不可数名词
a great number of修饰可数名词
a great amount of修饰不可数名词
a great deal of修饰不可数名词