You need to declare the nature of your business e.g. if you are in the trading business, then the nature of your business is Trading. If you are running a restaurant, then the nature of your business is Food & Beverage.
The definition of your business (or nature of business) will be shown on the Business Registration License, and it should not consist of more than 60 characters (including space between words).
Your nature of business can be brief but shouldn’t be too vague. The Inland Revenue Department expects your nature of business to be descriptive enough so it is clear what you do. For example “Trading” or “Consulting” would be too general whereas “Trading Clothes” or “IT Consulting” are acceptable.
Said that, it is not necessary to spend too much time on your nature of business as by law, companies are authorized to exercise in any legal business whatever their definition of business is.