Yes, grammar is important. So is sentence structure and punctuation and all that great stuff. But it's also important to know some of the tools of the writing trade, and today's tool is the anachronism.
Usually, we easily identify a word’s part of speech, but a given word’s grammatical category can shift, or one form of the word can differ in meaning from another, in a process called functional variation.
An introduction to constructed languages, language creation communities, constructed language users, and type of constructed languages. Examples include Esperanto, Klingon, Tolkien's Elvish, the Akana languages, and others.