The phrase 'rule business' can be interpreted in multiple ways, depending on the context. If it denotes the idea of being in charge or taking control, then synonyms such as 'manage', 'govern', 'lead', 'control', or 'supervise' could be used. If it means being firm or strict in enforcing regulations or policies, then words such as 'enforce', 'administer', 'implement', 'execute', 'maintain', or 'uphold' could be suitable. Alternatively, if it signifies entrepreneurship or running a company, then synonyms such as 'operate', 'manage', 'conduct', 'run', 'oversee', or 'direct' could be used. It all depends on the context in which the phrase is being used.