代名詞と限定詞 - 断定的な不定代名詞と限定詞

used to denote a certain, but unspecified, portion or selection of things or people

いくつかの, 何人かの

a person who is not mentioned by name

誰か, 人

a person whose identity is not specified or known

誰か, 一人

used to mention a thing that is not known or named

何か, 物

used to express an unspecified amount or number of something

いくつかの, いくらかの

used to refer to an unspecified selection within a group or category

いくつか, 特定の