Here are some references for Non Deductible Expenses if you are getting stuck.
Non-Deductible Business Expenses
Non-deductible business expenses are activities you or your employees pay for that do not fulfil the conditions above. This includes personal expenses such as travel or entertainment not related to the running of the business, and capital expenses such as expenses incurred to incorporate a company and purchase of fixed assets.
For examples of Non-Deductible Business Expenses please visit: https://www.iras.gov.sg/irashome/Businesses/Companies/Working-out-Corporate-Income-Taxes/Business-Expenses/
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