  We describe two ``semantically-oriented'' dependency-structure formalisms,
U-forms and S-forms. U-forms have been previously used in machine translation
as interlingual representations, but without being provided with a formal
interpretation. S-forms, which we introduce in this paper, are a scoped version
of U-forms, and we define a compositional semantics mechanism for them. Two
types of semantic composition are basic: complement incorporation and modifier
incorporation. Binding of variables is done at the time of incorporation,
permitting much flexibility in composition order and a simple account of the
semantic effects of permuting several incorporations.
