Is there any way to tell for sure whether this means "Her children eat breakfast" as opposed to "Her child eats breakfast?"
Some words in Swedish are the same in singular and plural, but in most sentences you will be able to tell from the other words used which it is. For example, 'Hon äter frukost med sin barn' would indicate one child. 'Hon äter frukost med sina barn' would indicate multiple children. Likewise 'Vem är din barn?' would indicate one child, 'Vilken är dina barn?' would indicate more than one child. Hope that helps!
Barn is an ett-word, so it should be: "Hon äter frukost med sitt barn", "Vilket är ditt barn" and "Vilka är dina barn".
In general it helps. But in the case given neither "hennes" nor "barn" are clear in that question. Both can be singular and plural. (or did I misunderstand anything?)
Miriam, the Swedish we are given here is ambiguous. It can mean either of the following:
1. Her children eat breakfast.
2. Her child eats breakfast.
Compare the following English sentence, which is similarly ambiguous for similar reasons:
Her deer ate breakfast.
How many deer? We do not know from the noun, and the verb here does not tell us either.
I like the word "frukost" because it's kind of like in German, where we say "Frühstück", literally meaning "earlypiece".
yes, except henne refers to an object. For example, "Han tycker om henne." which means He likes her. The pronoun, her, does not own anything, so it is just a regular pronoun. Hennes is a possessive pronoun. For example, "Det ar hennes hund." Which means It is her dog. The pronoun, her, owns the dog, so it is possessive.