First, at the time of the New Testament, Greek was written in uppercase letters only. That's important because too many times I have heard people in Bible classes say something like, "Well, it has to be talking about the Holy Spirit because it's capitalized." ALL the letters are capitalized. In fact, in our culture we would be thinking that God is yelling at us, which of course He isn't, though I am sure He would like to fairly often. When the translators see the word "SPIRIT" they must make the decision whether it means the Deity or an attitude, like school spirit or a spirit of unity. These men are often so reverent that when they are not certain which it means, they will capitalize it to make sure they do not insult the Holy Spirit. That was the mindset of the very early translations and translators, a wonderful mindset to be sure, but one that can and has often caused misinterpretations. Be careful with those capital letters and don't make any arguments based upon them.
Second, no spaces existed between words and there was no punctuation. In the classic example, imagine you saw this sentence: ISAWABUNDANCEONTHETABLE. Now, is that "I saw a bun dance on the table," or "I saw abundance on the table?" The translators go primarily by context as well as common sense. I have never seen a bun dance on the table, neither the waltz nor the polka, but I have seen many feasts where indeed there was abundance on the table. That's why the translators are acknowledged scholars. They are used to handling that ancient language and all its peculiarities.
The point about punctuation is also important. Everyone knows that Paul had a penchant for long sentences, as in Eph 1:3-14. That is one sentence. The newer versions cater to our culture's desire for what I call "business writing"—short sentences that are simple to read and understand. That's fine in business writing. It is NOT fine when we are discussing important and profound subjects. You should always keep an older version handy when you are studying from a new one (NIV, ESV, etc.) so you know exactly what was written and see the connections. If your version includes a phrase or words four sentences later that were actually in the original one sentence, you may miss those connections. Yet these are the markers for the beginning and end of a thought. Yes, it is more difficult to read and comprehend a long sentence, but this is your soul we are talking about. You are supposed to be so deeply interested in these things that you will pore over them for hours, not give them a quick scan and move on. The New Testament is not a collection of sound bites!
Now about those italics. Words written in Italics are supposed to be words "not actually in the Greek." Many times those words are implied or even necessary to the Greek word they support, another thing those scholars know that we don't. (If you took Latin in high school like I did, this probably makes perfect sense to you.) When we say, "That italicized word is not there," a majority of the time (one scholar told me 99%), we are wrong. It has to be there because of the word choice by the author. Please be careful when you start spouting off about a language you neither understand nor speak
Having said all this about Hebrew and Greek, remember that very few points can be made from those languages that cannot be made from any language, including English. Our loving God would never have left us with something we could not understand and follow when He planned to judge us by it.