Are there different grammar rules for spoken and written English

Spoken and written languages have important differences, even more than the obvious distinction in physical form. These other differences center around usage, and arise out of the fact that speakers and writers are functioning in different communicative situations. There are also differences in language structure: the grammar and vocabulary of speech is not the same as that of writing. The two modes of communication function quite differently and their status is not the same. Written materials can be legally binding and are also afforded a kind of respect which is rarely accorded to speech. Written English provides a standard that is valued by society. Its relative permanence and wider circulation also differentiate it from speech. Electronic mail has changed writing to become more interactive and there are also mixed media which overlap speech and writing. As far as grammar goes, the spontaneity and speed of most speech exchanges make it difficult to engage in complex planning. The pressure to think while talking means that speech contains looser construction, repetition, rephrasing, and comment clauses. Intonation and pause divide long utterances, but sentence boundaries are less clear. Facial expression and gestures help convey meaning in speech, as do nuances of intonation, contrasts of loudness, tempo, rhythm, and tones of voice. The lexicon used in speaking is often more vague and it also includes more slang, euphemism, and other informal language. The answer, then, to the question is that the grammar is different because of the different structure and function of speech as opposed to writing.