As a writer and editor by profession--?and an avid reader?--?I often see errors creep into writing that make me wonder, "Why didn't the author take a few moments to check and correct his or her work (or at least have someone cast another pair of eyes on it)?"

Knowing how to write well is a skill that is not only not fading but is assuming even greater importance in today's hyperconnected, always-on world.

Landing a job, closing a deal, inspiring employees, wooing top talent: These all require the ability to communicate well through writing.

Clear, impactful, and grammatical prose makes you look professional. Spelling and punctuation mistakes, vague or misused words, and other writing gaffes make you look, well, unprofessional.

Here are eight common writing mistakes that you should avoid?--?or correct?--?if you want your writing to stand out for the right reasons:

1. Misspelled words

With spell-checking functions built into word processing applications, free online dictionaries, and an unlimited supply of well-written, well-edited content available for free on the internet, there's no excuse for misspelled words. Yet it remains one of the most common writing mistakes I see people make.

So crack open an old-fashioned dictionary, or hop on Google or your online publication of choice, and enter the words that you're unsure of to see how they should be spelled.

2. Inconsistent spelling and punctuation

Nineteenth-century essayist and poet Ralph Waldo Emerson once said, "A foolish consistency is the hobgoblin of little minds." When it comes to writing well, however, I respectfully disagree: Consistency of spelling and punctuation is the mark of a professional writer.

If you prefer to write B.A. rather than BA as an abbreviation for Bachelor's Degree, use B.A. consistently throughout your entire résumé (or LinkedIn profile). Don't toggle back and forth between the two.

3. Wrong usage

Another problem that crops up frequently is the use of the wrong word in the wrong place. The culprits are often words that sound alike but mean very different things. For example, using the word "compliment," when you meant "complement"; writing "discreet," when you meant "discrete"; or using "precede," when you were supposed to write "proceed."

4. Confusing contractions with possessive pronouns

Another common problem I see?--?which can easily be fixed?--?is confusing contractions with possessive pronouns. These words might sound the same, but they are, of course, very different:

  • It's / its
  • They're / their
  • You're / your
  • Who's / whose

5. Weak qualifiers

"Sort of," "somewhat," "kind of," "rather," and "pretty much": these words water down your prose and dilute the impact of your message. Hit delete whenever they make an attempt to sneak into your writing.

William Zinsser, author of On Writing Well, the classic guide to writing nonfiction, had this to say on the matter: "Don't say you were a bit confused and sort of tired and a little depressed and somewhat annoyed. Be confused. Be tired. Be depressed. Be annoyed. Don't hedge your prose with little timidities. Good writing is lean and confident."

6. Sentences that go on and on

I often see writers try to pack several messages into a single sentence. But this muddies the message and confuses the reader. Long sentences that try to convey too much information become convoluted and unclear.

On this point, Zinsser advises: "If you find yourself hopelessly mired in a long sentence, it's probably because you're trying to make the sentence do more than it can reasonably?--?perhaps express dissimilar thoughts. The quickest way out is to break the long sentence into two short sentences, or even three." 

7. Walls of text

Another easy fix that will improve your writing: Break-up long paragraphs?--"walls of text," I call them?--?into shorter, easier-to-consume nuggets.

Zinsser suggests: "Keep your paragraphs short. Writing is visual?--?it catches the eye before it has a chance to catch the brain. Short paragraphs put air around what you write and make it look inviting, whereas a long chunk of type can discourage a reader from even starting to read."

8. Lack of focus

A parting piece of advice: Focus your message. Apply this principle to your writing regardless of word count, whether you're crafting a two-sentence email, a 600-word blog post, or a 5,000-word e-book.

Zinsser's view? "Every successful piece of nonfiction should leave the reader with one provocative thought that he or she didn't have before. Not two thoughts, or five?--?just one. So decide what single point you want to leave in the reader's mind."