What do German think when you use the wrong case?
Duolingo is very harsh if you get the case wrong but I was wondering what do actual German's think if you use the wrong case in a sentence? Like if I used "der" instead of "den"? Would it be very noticeable or would they just let it go?
It's very noticeable (well, unless you use Dativ instead of Genitiv after "wegen", I notice it and a lot of others do too, but A LOT of Germans don't even know you should use the Genitiv).
But while we do notice it, I can assure you we all know it's difficult (and even have a saying "Deutsche Sprache, schwere Sprache" - "German language, difficult language") and don't think anyone who we know learns German/isn't native is stupid for making mistakes with the cases here and there.
Some people might let it go, some might correct you (to help you, so you can learn).
Agreed... I'm not a native German speaker and I don't live in Germany, so I can't speak for regional attitudes, but I've been an expat for most of my adult life and almost 100% of my communication occurs across language barriers. People definitely notice when you make grammatical mistakes, even small ones, and I do think it's hard for people not to devalue your intelligence a little bit when you make grammatical mistakes. It's tough as a foreigner because people always treat you like you're a little bit dumb. But they do realize that you're a non-native speaker, and they generally understand that you've worked hard to learn a language (even if their first impulse is to laugh a little bit). Your accent is always going to make you stick out anyway, even if you manage not to make glaring grammatical errors.
I have some really brilliant friends in the country where I currently live, and I notice every grammatical and pronunciation error they make when they speak English with me, but my overarching estimation of them is that they're really smart. I might notice their grammatical errors when they speak to me, but afterward I just remember the content of what they've said. Some communities might be a bit more persnickety than others when it comes to non-native speakers, but being able to get your point across is the main thing. The more accurately you can speak, the more highly people will think of your intelligence--but even if you do make glaring errors, people get that you're a learner. (One of my closest friends in the country where I live is actually a super-successful artist with work in major museums all over the world. He probably wouldn't notice I existed if we both lived in America, since he's famous and I'm a nobody. He's fluent in English, but sometimes he mixes up words. I always notice, but any impulse to be a grammar nazi is definitely overridden by my respect for his work.) I'm always mortified when I make mistakes in speaking the local language, and I know people notice it, but they're generally really kind and forgiving--even if they laugh a bit.
I would assume much like using the wrong gender in Portuguese/Spanish/Italian... it sounds pretty bad.
der Haus das Familie... hummmm, must sound terrible.
This. There is something about little mistakes that I find endearing. Whenever I hear someone who speaks English as a second language make a mistake (such as using the wrong preposition) it reminds me that we are all human and we all make these mistakes when trying to learn another language.
Yes, cute in... like this guy: http://cwbblogs.com/cameroon12/files/2012/11/allo-allo-arthur-bostrom-as-officer-crabtree-2.jpg
Agree, it's not just a typo (most of the times anyway)... it's a cornerstone of the language.
Honestly, I think it depends on the context. Most other people here have said that it's very noticeable. That might be true for simple sentences, but even Germans sometimes get the case wrong for longer and more complicated sentences, so if you're speaking in a longer conversation and you make a one-time mistake with the case, I don't think most people would think much of it.
English has cases as well, so you can imagine how it would sound to you if someone were to say something like "Me talked to he" or "Him talked to I". It sounds bizarre. But in a longer sentence, like "The other day I met John, and him talked about how work is going", it doesn't stand out as much and you probably wouldn't dwell on it for very long because you'd get the idea. I think the same is true in German: they might notice it but they would understand what you mean and it wouldn't stand out much unless it happens constantly.
That said, you should still learn how the cases work, so it doesn't happen to you constantly. ;) But in longer sentences where it's not always easy to keep track of what case you're in because it shifts over the course of the sentence, it's not really a big deal.