essence：the most basic and important quality of something? ?
The essence of Macau is poker chips and entertainment.
如果將“poker chips and entertainment”看作是一個整體纺棺，謂語動詞就用單數(shù)；如果看作兩個個體剖张，就可以用復(fù)數(shù)辙喂。
The essence of various cryptocurrencies is blockchain technology.
1）The essence of startups is rapid growth.
The essence of start-ups is scalability/rapid growth.
2) The essence of a student is to acquire knowledge and make preparations for going into the society.
