Maybe this could help: https://en.m.wikipedia.org/wiki/Swedish_grammar
Some of it: Swedish nouns and adjectives are declined in genders as well as number. Nouns belong to one of two genders – common for the en form or neuter for the ett form – which also determine the declension of adjectives. For example, the word fisk ("fish") is a noun of common gender (en fisk)
Nouns have one of two grammatical genders: common (utrum) and neuter (neutrum), which determine their definite forms as well as the form of any adjectives and articles used to describe them. Noun gender is largely arbitrary and must be memorized; however, around three quarters of all Swedish nouns are common gender. Living beings are often common nouns, like in en katt "a cat", en häst"a horse", en fluga "a fly", etc.