Keiner vs niemand
I know there have been posts about this before, but I'm still not getting a solid answer. Niemand is only for people, whereas keiner can be used for objects and people? That is the most common answer I am seeing on the threads with this same question. I just had a lesson on Duo where it said "No one speaks" and the obvious answer out of the three was "keiner spricht". But since it is referring to a person could this instance be interchangeable with niemand and also be "niemand spricht"? I've always understood that the base "kein" is to negate a noun, but with the instance of 'keiner spricht' it sort of is the noun. Please help! I am getting so frustrated :(
Yes, "Niemand spricht." is also correct. I think I use "niemand" and "keiner" for people interchangeably, but for me as a native speaker "keiner" sounds more colloquial than "niemand", especially if "keiner" stands alone: "Es war keiner da."/ "Es macht keiner auf."
But sentences like: "Keiner meiner Kollegen erschien." / "Keiner von uns war darauf vorbereitet." are different, because they refer to a certain group, of which nobody does something. In these cases it sounds more natural for me to use "keiner".
I do not know any rule and i am sorry (and would be really interested in) if there are groups of sentences/ contexts in which you can not use "keiner" instead of "niemand", but maybe someone else can confirm or explain my "colloquial-feeling" of a lonesome "keiner".
Don't confuse 'kein' with 'keiner'. The first one is a negative form of the indefinite article 'ein'. The second one is a pronoun just like 'einer' and has the same endings as 'einer' depending on the case.
As far as his relation with 'niemand' goes, feel free to interchange them depending on flavor when it comes to persons. But use 'keiner' for objects as well. In written German, it more common to see 'niemand' for persons vs 'keiner', but in speech, you will hear 'keiner' more.
In keinem dieser neuen Häuser möchte ich wohnen
keines von beiden
keiner von uns hat es gewusst