"the books" means that these books have been mentioned before. Unspecified it should simply be "books".
There is no context here, so either way is valid.
I didn't provide an article for books and it was marked incorrect.
From now on, please copy&paste or screenshot your answer so we can help you find the real reason it marked you wrong.
"Books" should be just fine as there are no articles in Latin
Márcus et Corinna librós legunt.
Márcus Corinnaque librós legunt.
Did not accept “Marcus and Corinna are reading books”. ??? Read and are reading
That is also a valid translation. If you had no typos, then next time this happens, flag it and report "My answer should be accepted."
marcus and corinna read books is marked wrong what latin sentence does then translate to this english sentence
I really don't know what that isn't accepted, as it really ought to be.
It's not that difficult to pronounce a sharp R. So why does the pronunciation dude think the R in Latin is pronounced just as in American?
Is "read the books" different from "read books" in Latin?
No, Latin has no definite/indefinite articles. But if you wanted to be very clear, you could say "these/those books": "hi libri/illi libri".
"Marcus et Corinna read books" still not accepted!