8 common grammar mistakes that make you look dumb

By now, you must have seen President Trump's bizarre misspelling of … well, we're still not sure what word he tried to spell.

The word in question? "Covfefe"

It's possible the president meant to write the word "coverage" in a tweet that complained about how the media portrays him.

Soon after, millions of people took notice and poked fun at the president's blunder. A "word" like covfefe is easy to spot and dissect.

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There are other, more common words we often spell incorrectly and don't realize it. Will the gaffe make headlines? Probably not.

But in the business world, misspellings can hurt our reputation.

Here are eight classic examples.

It can sound like an "a" in "def-in-ah-tely" but it's spelled with an "i."

I see confusion over then/than all the time.

We write "then" when the topic is related to time or a sequence of events. As in, "I am going to the park and then to the store."

"Than" comes into play when we compare or assess. As in, "The comedian is funnier than I expected."

The trio are all so similar. When do we use each one?

Assure is to calm someone's nerves or tell them it's OK.

Ensure is to make certain.

Insure is to cover or protect someone in a financial sense.

I don't know when the apostrophe situation began, but I see the error all the time. Someone will write on Facebook, "So excited for all the concert's this summer!"

Nope. Incorrect. It's "concerts." Always has been.

Instead, we use apostrophes to show possession ("Danny's article has writing tips").

It's "between you and me." When we use a prepositional phrase (ex: between ___ and ___), we go with an indirect pronoun (ex: "me") instead of a direct one ("I"). Look, I don't make the rules. I just follow them.

Other options could be:

• "for you and me"
• "from you and me"
• "with you and me"

Another common mistake most of us don't think about. For example, "I learned a lot about the company and their approach to customer service."

Wrong. "Their" would refer to a plural noun but the noun in question is "company."

"I learned a lot about the company and its approach to customer service."

"Company" is singular. Always refer to your subject and then choose its or their.

A "principle" is a rule. A "principal" is a title like a high school principal.

Many people think it's "mispell" with a single "s."

But if we, as a culture, can't spell "misspell" correctly, then our grammar has a long way to go.

This article originally appeared on dannyhrubin.com.

Danny Rubin is the author of the new book "Wait, How Do I Promote My Business?"