一.Least是little的最高级，作副词和形容词来用
It happened just when I least expected it.
二.Least+形容词或副词，构成的最高级是“最不XXXX”的.意思
1.This is the least expensive method.这是最不费钱的方法
2.She has not the least experience.她毫无经验。注意not the least是“丝毫无XXX”的意思
三.名词least常用用法
1.A has little, B has less, and C has the least.甲没有多少，乙更少，而丙是最少的。
2.He is not in the least touched.他一点也没被碰伤。
3.You should at least tell me. 你至少该告诉我啊。 at least=至少