Some masculine words have specials rules, taking a different plural ending. This happens when these words follow a number or expressions such as колко (how many?) or няколко (a few). In these cases, they will end with -a.

“един месец” - one month

“два месеца” - two months

“един ден” - one day

“няколко дена*” - a few days

This is called the numeral plural or counting form (бройна форма). This only applies to masculine nouns that do not represent people.

  • Bulgarians often use “дни”, the normal plural, instead of “дена”, the numeral plural. Therefore we’ll consider both “два дена” and “два дни” as correct. “Дни” is much more commonly heard, despite “дена” being the grammatically correct version.

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