person that has visited you far more than with "you should visit us again". "ought to" is sometimes a synonym to "cannot avoid". "should" is almost never a synonym to "cannot avoid". "That ought to be easy." expresses the expectations that might not be true. For example, you tried to solve a problem, but it just doesn't go the way you want. "That should be easy" contains far less negative feelings. (In this case "That ought to be easy." is almost equal to "That should've been easy") With correct usage, both "should" and "ought to" have their very precise places in modern English. What makes confusion is that people are using them carelessly, as is the case with other expressions or verbs in English. With "ought to" instead of "should", you can make your thought more precise, but you can as well make someone puzzled why you have used "ought to" at all. If someone cannot feel the difference between "ought to" and "should", it is safe to always use "should". Actually, people or learner of English tend to do so, thus it looks that "ought to" is rare. It is not rare, it only has a more specific usage than "should". "Ought to" almost always holds a strong warning about the consequences, or emphasizes good features of consequences if it is something positive. I'm glad to see your long response and thoughts on this. My interpretation of "ought to" has been equated with "might want to." Were I to