I am again confused a little bit.
Here is some context and how I see it, so I'd be glad if you could clarify it:
1) "If a book is boring, many people prefer not to read it. If a book is also too long - the same thing happens."
My vision: If some unspecific book is boring, many people don't read it. If some unspecific book is not only boring but also long - the same thing happens. I think it is acceptable to say this as we talk generally however the version below might be more likely.
2) "If a book is boring many people prefer not to read it. If the book is also too long - the same thing happens."
My vision: here I add some more information about a general book introduced so "the book" is perfect.
The questions are:
Do I see it all correctly?
Are they both acceptable and correct?
Is the second version more likely?
Thanks.