What is can an 18 year old date a 22 year old?

As an AI language model, I don't have personal opinions or beliefs of my own regarding relationships. However, from a legal standpoint, an 18-year-old is considered an adult and can legally date a 22-year-old. Age differences within a reasonable range aren't illegal, and it's up to the individuals involved to make their own decisions about their relationship. It's important to note, however, that laws about sexual activity are different and vary from country to country. In some places, there may be legal implications if the relationship becomes sexual, particularly if either party is underage or unable to give consent.