Free How to Learn a Foreign Language by Graham E. Fuller Page A

and many other languages is that some others fuss a lot with the ends of nouns. In English, whether you've ever realized it or not, we rely largely on word order to convey meaning. “The dog bites the cat” and “The cat bites the dog” have very different meanings. So what? Everyone knows that if you change the word order you change the meaning.
    But for a lot of other languages this simply isn't so. They depend largely on endings on the words to make the meaning clear. In Russian, for example, it is quite possible to reverse the order of “dog bites cat” to “catbites dog” and still mean exactly the same thing: the cat got bitten. Why? Because in Russian the word order isn't all that important. In Russian you have to put an ending on the nouns to indicate which is the subject and which is the object, that is, who is the “biter”, and who is the “bitee”.
    How? In Russian a large body of nouns end in “-a” when the word is the subject (or “biter”) of the sentence. That same noun changes its ending to “-u” when it becomes the object of the sentence (or the “bitee”). So the word “koshka” (cat) becomes “koshku” when it moves from “biter” to “bitee”. In the same way “sobaka” (dog) becomes “sobaku” when it becomes the one that gets bitten. So in Russian it really doesn't make much difference exactly what the word order is, the meaning is still the same. In Russian, Sobaka kusayet koshku and Koshku kusayet sobaka both mean “The dog bites the cat.” But in English word order makes the crucial difference about who gets bitten.
    Of course, not all of you will be studying languages in which the word order is as unimportant as it is in Russian. But many languages in the world behave in the same way, preferring to use signals or codes, or endings—or whatever you want to call them—at the end of words to signal to you about who is doing what to whom. Other languages which do this to some extent or another include German, Latin, Greek, nearly all the Slavic languages (Polish, Czech, Serbian, etc.) Turkish, Persian and hundreds of other more obscure ones.
    English, French and Spanish, have almost totally dropped these endings on nouns yet still cling on to them when it comes to pronouns—those little words that “stand in” for nouns. In English we make a distinction between most subject and object pronouns:
    Subject Pronouns: I you he she it we they
    Object Pronouns: me you him her it us them
    Boy chases girl.
    He chases her.
    We don't say “He chases she.”
    We've just talked about one kind of ending here, the ending used to denote the subject of the sentence as opposed to the direct object. But many languages have more than just that one kind of ending, or “case”. Another very common case is called the genitive case, or more commonly in English grammar, the possessive case. As you might guess, it is the ending that denotes possession.
    We have an ending to denote possession in English, just as do most of the Germanic languages, Slavic languages, and many others in the Indo-European family (but not the Romance languages for some reason). In English the ending is “-'s” (apostrophe s). “The dog's bone” means “the bone of the dog.” In fact, “the bone of the dog” is the only way you can express it in Romance languages like French or Spanish. Many other languages that use the possessive case, however, prefer to put it the other way around, by saying “the bone dog's” which means, “the bone of the dog.”
    In still other languages, endings tacked onto nouns take the place of separate English prepositions, such as “to” “from” and “at”. Turkish nouns provide a good example. Every noun in Turkish can have the following case endings attached to it.
    ev = house
    evin= of the house
    eve = to the house
    evi = the house (direct object of an action)
    evde = in the house
    evden= from the house
    From this you can see what the word “grammar” really