The way we put words together to make sentences is known as syntax. It’s easiest to consider the basics of syntax in terms of canonical sentences. A canonical sentence is a sentence of the simplest, and possibly commonest, kind. An example might be William drives. Simple enough. No negation. No question. A simple statement. Three non-canonical versions, just to give an idea of the difference, would be Does William drive? William doesn’t drive and Doesn’t William drive? There are seven ways in which canonical sentences can be structured in English. The first two are Subject-Verb and Subject-Verb-Object.
In the sentence William drives we can identify what each of the two words does by giving them names. William is the Subject and drives is the Verb, so we can say the sentence has the structure Subject-Verb or S-V. William does something and drives describes what he does. In this sentence, drives is known as an intransitive verb. The sentence is complete in itself. As far as the structure of the sentence is concerned, William doesn’t need to be driving anything in particular.
Now, contrast that sentence with William drives a Mercedes. We can already identify the first two words as Subject and Verb. What of the next two words, a Mercedes? Well, they clearly tell us the make of car William drives, and we can perhaps see that in a way William does something to a Mercedes. He drives one. Where the sense of the verb carries over to a further part of the sentence in this way, we say that the verb is transitive. This structure is known as Subject-Verb-Object, or S-V-O.
We find the same structure in the sentence The dog bit the man. That tells us something about the effect of aggressive canine behaviour on a male member of the human race. If we said The man bit the dog, that would not mean the same thing at all. That is because English is an analytical language. That means it shows the relationship between words by their order in the sentence. It contrasts with an synthetic language like Latin, which shows such relationships not by word order, but by different endings, or inflections on words. Another language that did the same thing is Old English, the language of England roughly from the fifth to the eleventh century. We see the most extensive remnants of the Old English reflectional system in Modern English pronouns.