1、原型不同:less的原型是little,fewer的原型是few。
2、用法不同:less用于修饰抽象、不可数的名词,如:There was much less noise in the park after the children left.孩子们离开后,公园里安静了许多。fewer用于修饰可数名词,如:The weather became worse andthere were fewer climbers.天气变差,爬山的人少了很多。