The paper provides an account of the semantic composition of perfect aspect sentences in German and English based on the assumption that the relevant semantic information is encoded in the lexical entries for past participles and perfect auxiliaries. These lexical entries are conceived of as in word-based theories of morphology and the lexicon. This is a novel approach to the compositional semantics of tense and aspect. The basic ideas concerning the semantic ingredients of tense and aspect are adopted and partially adapted from work by Wolfgang Klein. It is shown that the central facts of the interpretation of perfect sentences in German and English, both interpretive similarities and differences, follow from the denotations proposed for past participles and perfect auxiliaries and their composition by standard semantic operations (functional application, -conversion). Moreover, the semantic derivations suggested in connection with an information-structural consideration provide an explanation for what has been referred to as the “present perfect puzzle” (Klein), that is, essentially, the compatibility in German and the incompatibility in English of a definite positional past time adverbial with the finite present perfect.
