In support of Johanna Rubba's excellent clarifying statement on "BE supposed to" let me make two comments: [1] The OED gives, among its many historical meanings of "suppose," these two: "to expect" and "to assume." I think it would make sense to suppose (forgive me) that originally the expression "You are supposed to..." was no different from "You are expected to...." In other words, a passive construction. Not all passives have identifiable agents. We use the passive, for example, to indicate what people (or experts) generally do: "A copper pan is used when beating eggs." [2] The evolution of "BE supposed to" into a model (something that many seem to feel instinctively is happening, or has happened) can be discussed in another way (besides the historical perspective Johanna introduced). We can talk about word classes as defined by "prototypical" cases--examples that fit the category perfectly. Then we can refer to instances that fit the category imperfectly as non-prototypical cases. Thus, "old" is a prototypical adjective because, besides taking certain suffixs (-ness, -er), it can fit in either of these two syntactical positions: The _____ man seems very _____. "Old" has all the features of an adjective. But neither "alone" nor "main" are prototypical adjectives because they can only fit into one or the other of those slots: "His main enemy is very alone," but not "His alone enemy is very main." And "main" doesn't take "-ness" gracefully. Our discussion, then, would focus not on finding the right label, but on noting which features a construction posseses and which it lacks in relation to prototypical cases. And we can note that a non-prototypical part of speech may share characteristics of more than one part of speech. --Bill Murdick