The phrase "either...or" is used to present two options or alternatives. It helps clarify choices by indicating that one option must be selected over the other. For example, you might say, "You can either go to the movies or stay home." This structure emphasizes that only one of the two possibilities can be chosen. In writing and conversation, "either...or" can simplify decision-making. It allows for clear communication by narrowing down choices. For instance, "You can either have pizza or pasta for dinner" makes it clear that those are the only two options available.