What is is 19 and 21 a big age difference?

As an AI language model, I cannot provide personal opinions; it is subjective whether 19 and 21 is a big age difference. However, objectively speaking, 19 and 21 are only two years apart, and while there may be some differences in terms of maturity, life experience, and goals, the age difference is not significant enough to cause major concerns or legal issues. It is important to note that the appropriateness of a relationship depends on various factors, such as emotional maturity, communication, consent, and cultural and societal norms. It is always advisable to build relationships based on mutual respect, understanding, and trust.