"The boy does not have milk."
Translation:У мальчика нет молока.
But this sentence doesn't really have the verb «есть». :) It has «нет», which is used with a noun in the genitive case.
It seems strange to me how, in order for Russian translations to make sense, English people have to stick other words into the sentence.
What I mean is, this sentence literally translates to: "this boy no milk" or even "boy no milk". We have to stick in words like " has", "or", or "and" in order for this sentence to not sound like a caveman grunt to us. Why is this?
No, those are unrelated. «У» requires genitive (hence «у мальчика» 'at [the] boy's possession'), and «нет» requires genitive («нет молока» 'there is no milk). Those are completely unrelated to each other, and if you use them in other contexts, they will have other cases:
- У ма́льчика есть молоко́. 'The boy has milk.' (literally 'at boy's [possession], there-is milk'; молоко is nominative because you use nominative with есть)
- В холоди́льнике нет молока́. 'There is no milk in the fridge.' (холоди́льнике is prepositional because в requires either prepositional or accusative)
This might not be explained yet, because sometimes Duolingo introduces new words without explaining them.
Russian nouns have several forms called cases.
Ма́льчик is the nominative case, it's used when it's a subject of the sentence (ма́льчик ви́дит соба́ку 'the boy sees a dog'; 'the boy' does the action of 'seeing', so it's the subject of the sentence).
Ма́льчика is either genitive or accusative case. The preposition «у», used to show the possessor, is used with the nouns in the genitive case. Note that the structure of the Russian sentence is different from the structure of the English one. In English, 'the boy' is the subject ('the boy does not have milk'), 'the boy' does (or, rather, doesn't do) the action of 'having'. In Russian, the structure is like 'at [the] boy, there-is-no milk'. This sentence doesn't even have nominative case, it uses a completely different construction.
Aside from being used with «нет» 'there is no' to show absence, genitive can be used to show possession: молоко́ ма́льчика 'the boy's milk'.
Ма́льчика can also be an accusative case. Accusative case is used for objects, that is, for something affected by the action. For example, in «соба́ка куса́ет ма́льчика» 'the dog bites the boy', 'the boy' is the object, he gets affected by the action of the dog (and the dog is the subject).
@luisamesquita02 - Correct.
"Мальчик" is in genitive case because it is modified by the preposition "у" (at, near, by, etc.). "У" always puts the word it is attached to in the genitive case.
"Молоко" is in genitive case because of the "нет". When you use "нет" to show the absence of something ("there's no X"), it puts that word in genitive case.
So, same case, just two different reasons why.