"dieses" takes an 's' ending as it's referring to a neuter Noun in the accusative. The plural would be "diese Bücher" i.e. no 's' on the end of "diese".
When would dies be used? And is there a "diesen" or "dieser"? This word is confusing me.
Well, "dieser" can be a determiner (so it indicates case and gender of a noun phrase), or a pronoun.
In each instance, it sort-of declines similarly to the definite article "the". So:
Nom: Masc/Fem/Neut/Pl = dieser/diese/dieses/diese
Acc: Masc/Fem/Neut/Pl = diesen/diese/dieses/diese
Dat: Masc/Fem/Neut/Pl = diesem/dieser/diesem/diesen
Gen: Masc/Fem/Neut/Pl = dieses/dieser/dieses/dieser
So your "dieser" and "diesen" are up there, too.
When used as a pronoun, "dieses" is often replaced by "dies". Also, "dies" can be used whatever the gender or number, in the sense of "this/these", so:
Dies sind meine Äpfel (these are my apples) Dies ist meine Uhr (this is my watch).
As a determiner, "dies" sometimes replaces "dieses" in writing, in the Neuter Nom/Acc, too.
Genug von dieser Grammatik!
So if I don't know what to use, do I just use "dies"? and it would mean the same thing?
Is Buch in the Dative case since it's receiving the action and is therefore the indirect object, or do I have my grammar wrong?
Indirect objects are when an action is done to or for someone-- her in "I brought her lunch" or "dog" in "I gave the dog water". (sorry, I haven't covered the Dative case yet so I'd almost certainly decline them wrong if I tried to give an example in German)
Here, Buch is accusative case and a direct object, the action being performed on it. Like "football" in "I kicked the football" or apple in "I bit the apple"
If we wanted to say "I write these books", which form would have been correct: "Ich schreibe diese Buch" or "Ich schreibe diese Bücher"?
Ich schreibe diese Bücher. Your first translation means "I write these (many) book (one book).
Shouldn't it be, "Ich schreibe diesen Buch" ? Because dieses the accusative pronoun applies that Buch is neutral noun, where Buch is Masculine.
If I were to turn to my sister, point at the clipboard by me, I'd say 'I am writing this book' as the book is not yet finished.
Were I to say 'I wrote this book,' that would indicate that it has been finished and therefore is incorrect.
I write this book isnt correct grammar, it should be i wtote this book, or i am writing this book.
duo tells me nonstop there is no -ing form in german. so it means 'I write' and 'i am writing' this book. which.. actually sounds like it should be a correct answer.
dein = yours or your euch = you (in prural form). In english we follow similar rule like I (singular), we(prural). But english doesnt follow the same in case of prural 'you' like German
I answered the question as" I write that book", and is given correct. But,as per the discussion, the answer " I write this book" or "I write the book"should be correct. How is this? Can someone explain?
Yes, they're all three correct.
German doesn't distinguish "this/that" as strongly as English does, and never made the split between "that" and "the" that English made several centuries ago, so those are still the same word -- the definite article and the basic demonstrative pronoun/demonstrative determiner are identical in German.