Forget lists of words and punctuation marks. If you really want to know if a text was written by AI, look for this particular sentence structure. For as long as people have been using AI to churn out text, other people have been coming up with “tells” that something was written by AI. Sometimes it’s punctuation that comes under suspicion. (The em dash is generally considered the shadiest.) Other times it’s words that robot writers seem to love and overuse.