As AI makes its way into the mainstream, people who write a lot (emails, posts, letters) are trying out chatbots as ChatGPT to help.

But while technology has advanced, it still has a long way to go—and sometimes, some words and sentence structures just don't feel right.

And according to one AI expertthere is a word that is a dead giveaway your email was written by ChatGPT.

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Paul Graham, co-founder of the startup accelerator company Y Combinator, posted on X this week that the use of the word “delve” is a red flag that the work was most likely written by ChatGPT.

My point here is not that I don't like the “dig”, although I don't, but that it is a sign that the text was written by ChatGPT. pic.twitter.com/2i3GUgynuL

– Paul Graham (@paulg) April 7, 2024

He referred to a chart by researcher Philip Shapira, which shows that the use of the word “sheep” from 1990 to 2024 in published papers and articles has increased nearly 18,000 times in the last four years.

Another data tool, AI Phrase Finder, places “delve” as the no. 9 (out of 10) most commonly used by ChatGPT.

“If you make demands that a piece of text be comprehensive in coverage, then you can't exactly blame ChatGPT for using a word like 'delve', which carries connotations of rolling up your sleeves and digging deep into a topic.” , AI phrase finder said. “However, it is definitely an overused word by AI.”

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According to Merriam-Webster, delve is a verb this means “to make a careful or detailed search for information” and “to dig or work with.”