Particles or markers in Korean tell us how a noun works in a sentence.:) "아름다운 순간(beautiful moment)" is a noun with the adjective "아름다운". The noun, 아름다운 순간 can be... 1. an object with the object marker '을'/'를' 아름다운 순간 = noun, 아름다운 순간을 = object e.g. 아름다운 순간을 (기억하다 = to remember) 2. an adverb with the time marker, '에' 아름다운 순간 = noun, 아름다운 순간에 = adverb e.g. 아름다운 순간에 (깨어나다 = to wake up) 3. a plural form with the plural marker, '들' 아름다운 순간 = noun, 아름다운 순간들 = the plural form of 아름다운 순간 e.g. 아름다운 순간들 (을 기억하다 = to remember) \^o^/

They only differ in the final letter (or syllable). -을 is an object marking particle, so you can use it with verbs that take objects. -에 is a location marking particle and more, and is used in sentences where you have to say "to" or "at", etc. -들 is the plural marker, it's not always used if the context is obvious that the word is plural.