d

d

The Korean letter "ㄷ" (romanized as "d") is a consonant in the Hangul alphabet, pronounced similarly to "d" or "t" depending on its placement in a word.

In this sentence, '대' (dae) acts as a prefix to '학교' (school) to denote 'university', showing its use in forming compound words related to educational institutions.

나는 대학교에서 공부합니다.

I study at the university.

Here, '대문' (daemun) specifies 'gate', with '대' (dae) emphasizing size or grandeur, used as a modifier to indicate the gate's importance or size.

큰 대문을 열어 놓았습니다.

The large gate was left open.

The word '대' in '대문제' (large problem) is not directly present, but the concept of '대' meaning 'large' is implied in the perspective of viewing or addressing a significant issue.

문제를 크게 보는 것이 중요합니다.

It is important to look at the problem in a big perspective.