I have this doubt about politeness levels towards strangers that are younger than me.
I'm currently using 존대말 (spelling?), standard politeness level, and 저 when I write them e-mails or talk to them. To be honest it is always a bit hard for me to use 저 because I usually used 나 plus ㅂ니다 when I first started to learn Korean in Korean school back then.
I was looking for tandem partners for Korean, i.e. Koreans that teach me Korean and I teach them German in return. They are normally 유학생 and younger than me.
My mother said I shouldn't use 저 towards them.
I wanted to know how you normally talk with people that you don't know well (yet) but are younger than you.
One of them is significantly younger than I am, probably more than 5 yrs younger, and the other one is 2 yrs younger than me (in chronological age).
Would I have to use 반말? Is 존대말 with 나 ok or would it look stupid for someone who is older?
Also when I met my Korean cousin who is 2-3 yrs younger than me and who I hadn't seen in 15 yrs. she was always flipping back and forth between 존대말 and 반말. Mostly using 반말 and normally using 존대말 when she felt guilty for being late etc.