不指定代替的是具体哪个(些)人或物的代词叫不定代词。
--Do you have a pen? 你有钢笔吗?
–Yes, I have one. 我有一支。(one在这里指一支钢笔,但未明确是哪支钢笔)
在句中,“one”未明确是具体哪支钢笔, one是不定代词。
常见的不定代词
some, any, no, some-- (如something),any--(如anyone), no—(如nobody) many, much,
a lot, a few, few, a little, little all, both each, every either, neither other,
another
many, much, a lot, a few, few, a little, little
all, both
each, every
either, neither
other, another
