For the note about not opening the transcripts, do we need to write in both English and Korean?

For the note about not opening the transcripts, do we need to write in both English and Korean?

you can just write english, but you can also just copy and print the sentence below for it. 



" Please do not open this envelope. Unofficial once it’s opened.


봉투에는 대학 성적표가 동봉되어 있으니 열지 말아주세요. 봉투가 개봉되면 사용이 불가합니다. "