Can I change "she’s fairly happy" to "she’s pretty happy"?
Native speaker’s answer
Rebecca
Yes, you can interchange "pretty" and "fairly" without impacting the meaning of the sentence. Both "pretty" and "fairly" are used to mean, a little bit or not completely. I would say, though, to avoid using "pretty" in this meaning in business or formal situations and use "fairly" instead. "Pretty" is generally viewed as an informal form. Ex: The article was pretty good. Ex: The article was fairly good.