Syntax looks at the rules of a language, particularly how the various parts of sentences go together. While similar to morphology, which looks at how the smallest meaningful linguistic units, called morphemes, are formed into complete words, syntax examines how fully formed words fit together to create complete and understandable sentences. Understanding a language's syntax is important for understanding what makes a sentence grammatically correct.
The Purpose of Syntax
Linguists and grammarians who study syntax are not necessarily prescriptivist, which means they do not attempt to tell people how to "correctly" form a sentence. Rather, they are descriptivist, in that they look at how people actually speak and then create rules that describe what a language community considers grammatical or non-grammatical. Syntax deals with a number of elements, all of which help to facilitate being understood through language. Without rules, there would be no foundation from which to discern meaning from a bunch of words strung together; whereas these rules allow for a virtually infinite number of sentences.
Word Order in Language Construction
Perhaps the most important aspect of syntax is how the various parts of speech connect together. Every language has rules that dictate where certain types of words can be used in a sentence, and how to interpret the resulting sentence. A new language learner has to understand how this word order is structured, which can be difficult for someone used to a different language.
In English, the basic order is "Subject-Verb-Object;" this means that in a simple sentence, the first noun phrase is the subject, and the subsequent predicate includes the verb phrase and may contain an object. This allows English speakers to understand that in the sentence "The boy kicked the ball," the "boy" is the subject, and therefore the one doing the kicking, whereas the "ball" is the object being kicked. If someone wrote the sentence, "The ball kicked the boy," the meaning would be reversed somewhat strangely, and "Kicked the ball the boy," would immediately be recognized as a violation of basic syntactical order and read as nonsense.
Not all languages follow this same order, however. In Spanish, for example, the order of the words is more flexible in most cases, and serves to shift the emphasis of a sentence rather than its meaning. Similarly, adjectives in English usually precede the word they describe, while they come after the described word in languages such as French.
Parts of Speech
Another aspect of syntax covers the various parts of speech that a language uses and separates the words of the language into these groups. Each part of speech in turn has various rules that may be applied to it, and other rules that dictate when it cannot be used. English, for example, makes use of nouns, verbs, adjectives, and other word types, while different languages may not have a separate class for adjectives or make use of classes not found in English. Thai, for example, doesn't distinguish between adjectives and adverbs, while Japanese has several different types of words that act as adjectives.
Run-Ons and Incomplete Sentences
Through an understanding of proper syntax, speakers and writers know how sentences should be broken up. When two or more sentences are improperly combined into a single sentence, it usually creates a "run-on." Similarly, a sentence that does not contain a full syntactic idea, such as "Swam quickly to the bank," is considered incomplete. Understanding linguistic rules allows speakers and writers to effectively communicate ideas to others.