Part of my fascination with "basic" words stems from my interest in developmental psychology and linguistics. I have now three children (my wife was actually in labor with our third as I was writing my last entry) and being an aspiring linguist I like to think about language from their point of view. What follows are all just my own observations; I haven't formally studied developmental psychology, though I'd really love to.
From a developing child's point of view, language seems to grow in two ways simultaneously. It moves from the particular to the abstract, and it moves from early and common experience to wider and more specialized experience. Thus, a child will first learn the words "circle", "triangle", "square", and only later learn the word for "shape"---I think about the same time they learn you can call things "chair-shaped" or "car-shaped". They might know, earlier, how to answer properly a question like "what shape is this?" when you point to a geometric shape, but before they realize something can be x-"shaped", they don't use the word "shape" themselves meaningfully. Much later (none of my children have reached this stage yet, my oldest being only 4 1/2) he will learn the word "form", which means the same kind of thing as "shape" but applies not just to physical things, but also to things like plots or arguments or grammatical patterns. This is one kind of growth in vocabulary and language.
Another kind is of growth is from the more common to the less common. A child will learn very early on words that apply to his ordinary, day-to-day life: "food", "clothes", "floor", "spank", etc. At a certain age, he starts taking a hard look around and noticing many things he doesn't know the word for, because they weren't terribly relevant to him at first. This stage (the "what's that called?" stage) never really ends, but is only a natural commensurate with broadening experiences.
Now, it seems to me that this same distinction is useful when thinking about words that can have multiple meanings or translations. I see three distinct patterns in words with multiple senses---if anyone can think of more, I would be happy to hear about it.
First, there are words which have multiple meanings simply because they are abstract, like the word "form". Abstract words can refer either to the abstract concept, or to any of the particular things from which the concept is abstracted. So, "form" can mean, depending on context, just the same as "physical shape", or else it can mean something more like "pattern". It is quite possible for another language to lack a word with precisely the same range of abstraction as our word "form", and so when translating to such a language from English, the word "form" will always necessitate a choice based on context.
Another kind of multiple senses a word might have represents a simple expansion of language referrents within a single vocabulary word. For example, the word "run" is first used to refer to a physical act of motion, but it is also extended to refer to what a politician does when he wants to be elected. Here you have what you might call a sideways rather than an upward expansion of meaning: a word goes from one concrete to a different concrete. Now this is typically done on the basis of some analogy: here the connecting idea is that of the race, of which a political campaign is one kind, and another kind of which is the sort you run physically. The connecting analogy, however, is often quite weak and may well not be understood at all by the person who uses the same word in two different ways.
A third kind of multiple sense is a sort of a combination of the previous two. A word may start with a simple and concrete meaning, but then also take on an abstracted meaning while retaining the basic meaning as well. "Shape" might be a good example, actually, as the word can be used as a synonym for "form", although you have more of a feeling of speaking figuratively when you use the word in that way. "See" is another good example, actually. It begins by refering to physical sight, but then also comes to mean any sort of knowing.
Actually, this is an excellent example, because it illustrates a very common way in which vocabulary is expanded: An abstract idea is represented by a word which, in its first use, refers to the most basic or primary instance of this abstraction. Sight, for humans, is the most important sense. It is the first and most basic way in which we come to know things; hence, "to see" is most naturally adopted as a synonym for "to know". I think this is the case, actually, in every language that I know.
Semitic languages have a lot of good examples of these. HLKH, "to walk," in Syriac (and I think in Hebrew) has also the meaning of "to proceed", as you might use in "to proceed to my next point"---walking is the first and most basic mode we have of proceeding from one place to another. The word for "to stand" in Hebrew (I forget it at the moment) also means "to begin", on the same principle: in a basic, physical sense, you typically have to stand up in order to begin anything. TOV, "to turn around" also means "to do again", or even just "again" or "furthermore".
English has, I think, fewer examples, proabably because it is so vocabulary happy, that if it could ever find a separate word for the more abstract meaning, it would do so. I would not be surprised at all, though, to find that originally the ancestor of the word "go" or "gehen" originally referred also to physical walking.
Ok, this post is already way too long, so I'll break off abruptly here and continue later. Next time, I'll try and draw some inferences for the task of translating from these three kinds of multiple senses.