The phrase "has got to" is often used to express necessity or obligation. However, there are several synonyms that can be used instead of this commonly used phrase. For example, "must" can be used to convey a sense of urgency or importance. "Need to" can be used to express a requirement or a duty. "Have to" is another variation that can be used to convey obligation or necessity. "Should" is another option that implies a recommendation or suggestion. Other synonyms include "ought to", "require", "be required to", and "be obligated to". By using these alternative phrases, you can add variety to your writing and avoid overusing the phrase "has got to".