adjective. we use adjectives with nouns, so we use articles with nouns.
we use the to talk about a specific thing. we use a or an to talk about a non-specific thing. some is the plural of a or an.
specific: are you reading the book i gave you?
non-specific: are you reading a book?
specific: when did the accident happen? the accident happened yesterday.
non-specific: how were you hurt? i was hurt in an accident.
the is the plural of the.
some is the plural of a and an. 