"ja" in the middle of a sentence
I've got this sentence:
Ein Haus ist viel zu teuer, das kann ja niemand bezahlen.
I don't understand what does this "ja" mean in this context. can anyone explain it to me??
Just to add on what minppangshi said, „ja“ in this context is acting as what is called a "modal particle". This just means it's a non-essential element in a sentence, whose meaning is not the same as when it acts out of this context. Other examples include aber, schon, denn, doch & bloß (there are others, but the jury's still out on exactly how many there are).
I spent quite a long time looking into modal particles to see what they mean, but they are really so context and emphasis dependent, that a modal particle can be used to tone down a request to make it sound less harsh somewhere, and in another context that same modal particle can be used to show shock and disbelief in a (possibly rhetorical) question.
So, my solution was just to stop studying modal particles and just sort of look out for them. I have watched a fair amount of German films and TV shows and it's funny; I can't really put into words the betterment of my understanding, but I have a better feeling for them and sometimes when I'm writing in German or talking to myself in German, a modal particle slips out every now and again (rightly or wrongly would be for others to decide :).
As AdamKean already said, 'ja' is used here as a Modalpartikel.
I'll try to explain it's meaning with an example.
Ein Haus ist zu teuer; das kann niemand bezahlen: -- The house is too expensive, noone can afford it. Just a normal sentence
Ein Haus ist zu teuer, das kann ja niemand bezahlen -- >The house is too expensive, it is normal that noone can afford it
Ein Haus ist zu teuer, das kann eben/halt niemand zahlen. --> The house is too expensive, it is normal that noone can afford it and the one you are speeking to should have known that.
Ein Haus ist zu teuer; das kann doch niemand bezahlen -- The house is too expensive, noone can afford it although it is implied that someone thinks it is affordable.
it expresses some kind of Evidenz (no idea how to translate this). There's a good book on Modalpartikel, but it is in German... https://edoc.ub.uni-muenchen.de/4877/1/Kwon_Min-Jae.pdf
The modal particle "ja" could probably be translated with "as we both know". It states that the speaker expects no disagreement with the listener, because the information presented is already known or obvious.
Usually, modal particles add a kind of meta-information to the sentence. They don't change the facts presented in the sentence, but the speaker takes into account what he and the listener think or know about them.
Modal particles are very hard to explain, because their meaning is very dependent on context. Here are some lengthy blogs about certain modal particles. However, instead of trying to understand them interlectually for each context, it is probably healthier to just go with the flow and try to pick them up as AdamKean suggests above.
This blog goes into depth about this list of modal particles (no "ja" yet): “eben and gerade” 2 Words of the Day “eben… and gerade” “nämlich” “allerdings” “noch” “da” “wohl” “übrigens” “mal” part 2 “mal” “zwar” “schon” “halt” “denn” “doch”