Today I'm going to explain the strange phrase you've read in Read and Understand section: "inversive Vav" ... turns Past to Future, and  Future to Past.

The explanation might sound even more confusing, but in fact it's very simple: there was no such thing in Hebrew as "Past Tense" or "Future Tense". These are modern Israeli Hebrew terms. Originally it rather was "Perfect" and "Imperfect" aspects. It is the Perfect which gradually developed itself to be used as "Past Tense", and that's Imperfect which we treat today as "Future".

Here is a very well-known text from the very first page of Torah:

בְּרֵאשִׁית, בָּרָא אֱלֹהִים, אֵת הַשָּׁמַיִם, וְאֵת הָאָרֶץ. וְהָאָרֶץ, הָיְתָה תֹהוּ וָבֹהוּ, וְחֹשֶׁךְ, עַל-פְּנֵי תְהוֹם. וְרוּחַ אֱלֹהִים, מְרַחֶפֶת עַל-פְּנֵי הַמָּיִם. וַיֹּאמֶר אֱלֹהִים, יְהִי אוֹר; וַיְהִי-אוֹר; וַיַּרְא אֱלֹהִים אֶת-הָאוֹר, כִּי-טוֹב .וַיַּבְדֵּל אֱלֹהִים, בֵּין הָאוֹר וּבֵין הַחֹשֶׁךְ; וַיִּקְרָא אֱלֹהִים לָאוֹר יוֹם, וְלַחֹשֶׁךְ קָרָא לָיְלָה. וַיְהִי-עֶרֶב וַיְהִי-בֹקֶר, יוֹם אֶחָד.

This whole section is telling us about something that happened obviously in the past. (According to my information, the Six Days of Creation happened in the past, but nowadays when the history is re-written every decade, you can't be sure of anything.) So, we see the verbs marked with yellow marker being in the "Past" form, and all the other (cyan) in the "Future" form, and all of them are telling us about the past events.

But let's look on it in a different way. Classic grammar of ancient Hebrew didn't have a notion of tense, but rather perfect and imperfect; therefore an adequate translation would be (don't be pissed off if it sounds a little awkward):

In the beginning the God had created (and not just created) the skies and the land. And the land has been (yet) chaotic, and darkness upon the face of the deep, and the spirit of God hovers over the face of the waters. And the God said:let there be light, and it was light. And God saw the light, that it's good; and God divided the light from the darkness.
And God called the light Day, and the darkness He called Night. And there was evening and there was morning, one day

As you can see, translating with either Perfect and Imperfect barely changes the meaning. And Perfect by its very nature means something that happened in the past (think how often you use perfect in English when you describe future: you will have written a letter , they will have done this again...) So, no wonder the language evolved to simpler constracts: Perfect became Past, and Imperfect became Future. After all, that's what the Past is: something complete, or Perfect. And the Future is something that hasn't been completed yet, meaning Imperfect.

Let's take a look on another portion, and this time it all is talking about the future:

וְהָיָה, כִּי-תָבוֹא אֶל-הָאָרֶץ, אֲשֶׁר יְהוָה אֱלֹהֶיךָ, נֹתֵן לְךָ נַחֲלָה; וִירִשְׁתָּהּ, וְיָשַׁבְתָּ בָּהּ וְלָקַחְתָּ מֵרֵאשִׁית כָּל-פְּרִי הָאֲדָמָה, אֲשֶׁר תָּבִיא מֵאַרְצְךָ אֲשֶׁר יְהוָה אֱלֹהֶיךָ נֹתֵן לָךְ--וְשַׂמְתָּ בַטֶּנֶא

And the translation (taken from here, I guess it's King James')

And it shall be, when thou art come in unto the land which the LORD thy God giveth thee for an inheritance, and dost possess it, and dwell therein; that thou shalt take of the first of all the fruit of the ground, which thou shalt bring in from thy land that the LORD thy God giveth thee; and thou shalt put it in a basket and shalt go unto the place which the LORD thy God shall choose to cause His name to dwell there.

Well, without going into details of old English grammar (which is not our subject here), the point is: the Imperfect aspect is talking about "what will happen":

תבוא - you will come to the Land

תביא - the Land will bring the fruits

יבחר - the God will choose a place for the Temple.

As to the Perfect aspect, it's talking about things as they will have been done, so it becomes an imperative:

והיה -and it shall be (will have been happened)

וירשתה - and you will have inherited her

וישבת -and you will have dwelled (therein)

ולקחת - and you will have taken

and so on. So, the Inversive Vav (וַו הָהִפּוּך) is playing more or less the role of modal verbs in English. It comes with a "not native" usage of the Perfect or Imperfect aspect: i.e., for Perfect it's natural to occur in the past; and Vav helps it to come into "unnatural" place.

But of course, when translating from ancient Hebrew to modern English, a clear understanding is more important than grammatic accuracy.

Another interesting point: some people claim that Israelis do not understand the biblical Hebrew, and suggest translating the Torah into the "Israelish". And the "inversive Vav" is brought as an example of difference between the languages.

As a person, who is not even native Hebrew speaker, but lived in Israel for more than a decade, I can assure that this statement is very far from true.

Yes, for a non-native Hebrew speaker (and a person who barely attented any religious ceremonies), it's a bit strange for the first time, when you look on the text like "וישבת" reading it in the context as "ואתה תשב", and you actually recognize that what you've learned in your Ulpan was very far from being complete. It sounds pretty much like King James' translation above; however, still, it's totally readable and understandible. For native language speakers it never appears to be a problem, because their "sense of language" is a bit different. (Some native Hebrew speakers have other problems with their own language, but that's a social problem rather then linguistic one.) At least the basic words are the same, there is no "thou shalt" words (I wonder how some of todays young Americans would understand that.)

As to difference between the modern and ancient vocabulary, and that to fully understand the Scriptiures you probably need to learn some words... have you ever been preparing for SAT?