Questions & Answers about Мама готовит еду, а папа изучает карту.
Why do the words for food and map end in -у (еду, карту) instead of their usual -а (еда, карта)?
This is the Accusative case in action! Because the food and the map are the direct objects—the things being acted upon—their endings change. For inanimate feminine words that normally end in -а, the ending changes to -у.
мама and папа also end in -а. Why don't they change to маму and папу?
Because мама and папа are the subjects of the sentence—they are the ones doing the cooking and studying. The subject always stays in its dictionary form (the Nominative case). Only the words receiving the action change to the Accusative case here.
Why does the sentence use а for "and" instead of и?
The conjunction а is used to show a slight contrast or to shift the focus to a new subject. It often translates closer to "whereas" or "while." When comparing two different people doing two different things (Mom cooks, while Dad studies), а is the natural choice.
How do we know to translate готовит and изучает as "is preparing" and "is studying" rather than just "prepares" and "studies"?
Russian doesn't have a separate continuous tense (like the English "is doing"). A single present tense verb like готовит can mean "prepares" or "is preparing." You just choose the one that sounds best in English based on the context!