There is nothing incorrect about, "I have hunger," in English. You are correct that the point is to learn how to speak another language. This is why, "I am hungry," should be translated into, "Ich habe Hunger," in German. That is true. But it is not the same the other way around, as there are two ways to say it in English.
No native speaker says "I have hunger." It's like how in Spanish, you say how old you are my saying "I have 20 years". Yes, you COULD say that in English, and people would understand what you mean, but the finer point is that nobody says it like that.
If you said "I have hunger", people would get what you mean, but the point is nobody says that. It's not standard English, it's not even from any dialect I've ever heard of, therefore it's wrong.
Agreed. "I have hunger" is a direct translation, and can be understood in English.
A lot of people here are saying that it is unnatural English. This is correct; I would never use the phrase at home. But I am not trying to learn English here, I am trying to kearn German! Direcy translations help me and others understand how sentences are constructed in the language. Otherwise, all im learning is how to translate one phrase into an english phrase, and that teaches me nothing.
We are learning German. So the most natural way to say any of these phrases, is most important in German, of course. When we are learning English, we can fine tune the nuances of that language usage. But Duolingo has to have a baseline and is constantly evolving with user feedback.
So, as far I undertood after reading this post, in german is natural say "Ich habe Hunger", meaning more literally "I have hunger" but at moment of translate to english you need to put it in more natural phrase like "i am hungry". i'm not native for english and in spanish "tengo hambre" is way more natural that "estoy hambriento", so the concept to "having hunger" was easier to think.