Here is yet another example of the subjectivity of language. Standard American English is an ever-evolving entity, and experts disagree on many aspects of what is "correct." Dictionaries and textbooks vary slightly when it comes to standards of usage, and it is often up to the writer to determine which rules to follow. When it comes to word choice, should you use toward or towards? Cannot or can not? If you're like most writers, you turn to the dictionary and discover that towards is listed as a "variant," which leads you to believe it is "nonstandard." What does that mean? Is it correct or not?
Dictionaries list nonstandard words to indicate that they are commonly used but are not necessarily correct. You'll also find jargon and colloquialisms in the dictionary, but you wouldn't use the word "ain't" in your essay just because it's in the dictionary. (Naturally, you could use it in dialogue.) In other words, err on the side of standard usage.
Standard American English is "substantially uniform and well-established by usage in the speech and writing of the educated and widely recognized as acceptable" according to Merriam-Webster. Based on that definition, we have put together the following list of standard and nonstandard words and phrases.