Korean particle 1 : ~에/~에서 (한국어 조사 ~에/~에서)

HI, guys! it's KCC. we are teaching many different students Korean , many of them find difficult to learn some of Korean particles, so we decided to make a video about it to help people studying Korean. particularly, we are going to learn '~에' and '~에서' this time ,which are the most common but the most difficult particles at the same time.
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Are your subtitles wrong? (K-Drama expressions you should know)