Désolée d'être si fatiguée.

Désolée d'être si fatiguée.

I'm wondering what the d' is doing in this sentence?  

Désolée = Sorry (f)

etre = to be 

si = so

fatiguée = tired (f)

For your reading and bookmarking pleasure:

From : https://www.lawlessfrench.com/grammar/adjectives-with-prepositions/

“Adjectives related to feelings, states of mind, and obligation are usually followed by de plus a noun or infinitive.”

See also:

https://grammar.collinsdictionary.com/us/french-easy-learning/prepositions-after-adjectives

Robert

Thanks for that. I tried searching google, but wasn't exactly what to search for to bring up what I needed. I kept getting everything unrelated. 

Happy to help. It's always nice to find a straightforward answer to a good question. Good for you for trying to find the answer online. Sometimes you have to be fairly specific to get the results you're looking for. In this case, something like, Why is désolé followed by de. The search I type most often is simply, this vs that, when I want to know why something is said one way instead of another. I get a very good answer 95% of the time that I search online, and easily have over 100 bookmarks. It also helps when you have the mindset to go down the bottomless rabbit holes.

Robert