Grammarly Does Not Detect Run-On Sentences


Posted by Jake Magnum | December 25, 2017 | Grammarly Flaws


I had noticed that Grammarly failed to notice a run-on sentence in a book I was proofreading for a client recently. It made me wonder if run-on sentences are something that Grammarly routinely misses.

I did some playing around and found that Grammarly, for whatever reason, does not notice when a writer has failed to separate two independent clauses properly, resulting in a run-on sentence. The following screenshot shows some run-on sentences that I typed into Grammarly. Notice how nothing has been underlined and how there are no “critical issues” or “advanced issues” counted in the bottom right-hand corner of the screen.

Self-Proofreading Advice - Grammarly Flaws - Run-On Sentences

This shows that we can’t rely on Grammarly to fix all our mistakes for us — even particularly glaring ones, such as the last sentence in the example above. It is always a good idea to have a second set of human eyes look over your work.