The paper is concerned only with those time adverbials that are not part of the Verb Phrase (free time adverbials). Taking the rule Adv -- Prep NP as part of the base, it is shown how different types of adverbials can be distinguished either by the syntactic features of the lexical items dominated by Adv or by configuration. Each #S# of the deep structure is allowed at most one free adverbial. Surface sentences with more than one free adverbial are derived either by conjoining #S#'s or by unfolding non-restrictive relative clauses within an adverbial. The latter type of derivation applies only to surface strings of adverbials of the same type, the former only to strings of adverbials of different types or to strings of adverbials of the same type joined by und. The purpose of this paper is twofold:' first, we are interested in the rules for certain time adverbials in a generative grammar of German, using the model proposed by Chomsky 1965; second, we wish to investigate the consequences of using the rule