so few 表示肯定还是否定,few ,little,a few ,a little呢

so few 表示否定,
few ,little,表示否定
a few ,a little肯定有人告诉我表肯定，同a few，只是 a省略了，就像the 和 a 不能同时用一样，我有点糊涂了~~不用困惑，so few 、few只能是否定语气