First and foremost God bless you for such a question, it does warm my heart to learn that, there are people out there willing to learn Arabic just to read the Quran, matter fact I have an American friend that I always tell him this " I pray you learn Arabic the way I do just to read the Quran" therefore God bless you,help you, and I'll pray for you. now back to your question, see nowadays we speak modernized Arabic, or you can call it a local slang, we don't care about the grammar no more, that's unfortunate obviously, in my country we speak in different ways, just like every other country, every city has its own way of talking, and most of the time you can see it's grammatically incorrect, but no one cares as long as its not mandatory. look at it this way, if you look up Shakespeare work, and compare it too, lets say John Green's work, you think they speak totally different languages! the choice of words is different, the word play is different, the sound is different, the Quran comes with the most perfect Arabic ever, even the Arabs at that time could not even criticize a word of it, that's why we have a lot of meaning, and explanatory books to translate the Quran, I am an Arabic native speaker, I live in Mecca, the center of Islam, and yet I struggle many times with some verses, and to say even more, there is a huge chunk of our society that does not understand most of the Quran, once again God bless you, keep pushing, you'll get it soon enough, and excuse my poor English, and if you ever need help with anything, just let me know.