When we're talking to our teachers we use -요 instead of -(스)ㅂ니다 in order to be better prepared in most situations, I guess, and also because that was our first approach to grammar and it probably would've been weird to switch to honorific language after a year you've known someone. But I guess koreans use honorifics when they're in class, right? Anyway: how should I thank my teachers? Should I use 감사합니다/고맙습니다 even if I use -요 all the time or should I use 감사해요/고마워요 to be coherent? What's the feeling I'm giving?

Question

kida2d · Answer

I use both 니다 and 요. e.g.) 잘 잤어요. 감사합니다.
I dont know about others, but to me, it sounds more natural, polite and frendly. I often use 요 when storytelling. btw, 니다 is super polite.
perhaps, you would look like a robot or too stiff if you use it too much in a conversation. Anyway, i think you need to use 감사합니다/고맙습니다 to teacher and professor or elders.

kida2d · Answer

@geomicocci no worries, all good :)) 괜찮아용~^^