There seems to be a perception that writers have perfect grammar and professional writers never need an editor. The truth is, writers still make mistakes and as much as we try and avoid as many as we can, they still seem to pop up. As writers, we need to remember that we are only people with a passion for writing, but no one is perfect. Here is a list of 11 of the most common writing mistakes writers (and everyone else) make.
Via https://www.justpublishingadvice.com/11-common-spelling-and-grammar-mistakes-writers-make/