a lot,a lot of,lots of哪个是可数名词,哪个不是可数名词

a lot 单独使用 如：Thanks a lot 。a lot of =lots of 后面既可以跟可数名词复数,又可以跟不可数名词；如：There are a lot of trees on both sides of the road 。There are lots of fish on the stand (货摊）。希望可以帮到你!