To obtain the plural form from the singular form, add "ra" or "der" to to nouns (and pronouns) representing people and "guli", "gulo", or "gula" to inanimate objects.
Examples:
chele - chelera --- boy - boys
boi - boiguli --- book - books
Nominative case: no ending.
Possessive case: add "r" or "yer".
Locative and Instrumental case: add "e", "te", or "y".
Examples:
babar kolom -- father's pen
mayer gari -- mother's car
apnar skule -- in your school
dillite -- in Delhi
kolkatate --in Calcutta