Hello Jisoo,

Here are my answers to your questions:

1. "Inheritance"

He received a large inheritance from his father. 
그는 많은 돈을 아버지로부터 상속 받았다. 
 
He received a large fortune by inheritance from his father. 
그는 많은 돈을 아버지로부터 상속 받았다. 
 
위 예시 둘 다 괜찮나요? 어색한 부분은 없나요?

-> Both sentences sound fine to me.


2. "Obligation" _의무 관련 단어들 정리해보았는데,,, 각각의 차이를 잘 모르겠습니다. Would you show more details of these words?

1. Responsibility : 맡아서 해야할 ‘책임, 의무’. I will take responsibility. 제가 책임을 지겠습니다.
2. Duty : 직무상, 도덕적으로 마땅한 의무 ; We fill it is our duty.
3. Commitement : 약속하고 동의한 일에 대한 ‘책임, 책무’ ; 
4. Liability : 법적인 ‘책임, 의무’
5. Obligation : 도덕적, 법적 강제성으로 지켜야 할 의무 (약정서에 많이 나옴)


-> I think the definitions in Korean are all accurate. The connotation differences can widely vary depending on the context. I strongly suggest looking up these words on Google News section and read the sentence to understand why/how the term was used.



3. "postponement"

많이 못 보던 단어 같아서, 주로 어떨 때 쓰는지 느낌이 궁금합니다.


-> Indeed not a very common word. You definitely say “the meeting/event is postponed” but the word ‘postponement’ isn’t used very often. Perhaps a formal document.


4. 꽤 잘 하셨습니다만 당신이 최선을 다한 작업이라고 보기는 어렵습니다.
You did a great job however it is hard to think you did your best.
로 영작하였습니다.
이런 어렵다라는 표현을 쓸 때 hard 와 difficult 용법차이가 궁금합니다!

-> In this context, they are perfectly interchangeable.


I hope it helps.

Best regards,

Mason U, CMI-Korean
Business Interpretation and Translation in Korean (BIT-K) Instructor