There is no such word as ain't or Never end a sentence with a preposition . For linguists, grammar is simply the collection of principles defining how to put together a sentence. Every language has restrictions on how words must be arranged to construct a sentence. Such restrictions are principles of syntax.
Every language has about as much syntax as any other language.
The syntactic principles of a language may insist on some order of words or may allow several options. Even when a language allows several orders of phrases in the sentence, the choice among them is systematically regulated. For example, there might be a requirement that the first phrase refer to the thing you're talking about, or that whatever the first phrase is, the second must be the main clause verb. Not only does every language have syntax, but similar syntactic principles are found over and over again in languages . However, there is another aspect of grammar in which languages differ more radically, namely in morphology, the principles governing the structure of words.