I revise cover letters for my clients all the time (at no additional cost), and this is one of the most frequent errors I see when they're submitting a manuscript to a journal.
Typically, the first sentence in a cover letter will introduce the title of the manuscript, saying something along the lines of:
We are pleased to submit our research article, entitled "The Mating Habits of the Tsetse Fly," for consideration of publication in Insects Today."
So what's the problem here?
The word "entitled" essentially means to deserve something. For example, you're entitled to basic human rights, and you're entitled to respect. The word can also have a negative connotation, as in "That brat is so entitled."
However, a manuscript cannot be entitled anything. It's the completely wrong word to use in the context of a manuscript submission cover letter. It's an innocent mistake and it's easy to fix.
The appropriate word is actually "titled," which means to be named.
So the correct usage in the first line of a cover letter would be:
We are pleased to submit our research article, titled "The Mating Habits of the Tsetse Fly," for consideration of publication in Insects Today."
I hope you find this tip helpful. Having grammatical errors in your cover letter is embarrassing. Getting a second set of eyes to check your work for such mistakes can make a big difference.
If you're in need of an editor for such help, please email us at firstname.lastname@example.org and we can get started right away.
Bonus Tip: The title of the journal should be formatted in italics.