Things that are difficult to say when drunk:
Preliminary - Anesthetist.
Things that are VERY difficult to say when drunk:
Rhipidistian-Amphibian - Sphygmomanometer.
Things that are Impossible to say when drunk:
No more booze for me, I've had enough - Oh I couldn't, nobody wants to hear me sing karaoke - Thank you, but I don't dance well - I'd love to make out with you, but we should get to know each other first.