"а" implies contrast as far as I'm aware, i think it means "and" just like "и" but suggests the meaning of "but" or "whereas" это мама и это папа - this is mum and this is dad это мама а это папа - this is mum, whereas/but this is dad

(i am a total beginner but i saw an explanation like this somewhere so I'm not sure if the examples are correct but hopefully the definition is accurate(

"мам" and "пап" is colloquial form in russian.

the translation is 'mama' though.

Because father is the first and mother is the second

"and" in russian is "и". "a" is "один". For example: "одна ручка" - "a pen".

The "ручка И карандаш" - "pen and a pencil "

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