The most telling sign is when they don’t make sense — for example right here. A human puts em dashes to emphasize the break in thought or rhythm. Where there i

The most telling sign is when they don’t make sense — for example right here. A human puts em dashes to emphasize the break in thought or rhythm. Where there is already a break in thought or rhythm a human would just write a comma or nothing. Another tell is what is inside the em dash. It often doesn’t logically follow – like an ad on a radio show.