some vs many

some and many both are adjectives.

Word	Noun	Adjective	Verb	Adverb
some	No	Yes	No	Yes
many	No	Yes	No	No

some (adjective)	many (adjective)
(quantifier) used with either mass nouns or plural count nouns to indicate an unspecified number or quantity	a quantifier that can be used with count nouns and is often preceded by `as' or `too' or `so' or `that'; amounting to a large but indefinite number; quantifier, plural pronoun; quantifier, plural
remarkable
relatively many but unspecified in number

some (adverb)	many (adverb)
(of quantities) imprecise but fairly close to correct