I'm 'grateful' (to you) for this opportunity. = I'm 'grateful' to have this opportunity. = I'm 'grateful' that I have this opportunity.
expressing my 'gratefulness' [=(more commonly) 'gratitude'] for this opportunity
The college 'gratefully' [='thankfully'] acknowledges your donation.
(..) but how can such a man just disappear? (SCOFFS) (BJORN SIGHS) ASLAUG: Go and eat and drink after your long journey, Thorhall. We are grateful for your visit. I have to tell the boys. Where are they? They went up to the cabin to hunt. (SIGHS) (DOOR CLOSES) UBBE: Ivar. Wake up. (..)2016 TvShow: Vikings Title: The Last Ship Season: 4 Episode 10