The verbal categories of aspect and tense, however different in their grammatical expression, are more and more reduced, at least ultimately, to the common notional concept of ’time’, which is linguistically realized either as 'interna? time, i. e. aspect, or as ’external’ time, i. e. tense. On this point there can be cited a whole series of theoretical opinions professed by various scholars in the last fifty years, from Koschmiedcr (1929: 13) and Guillaume (1929: 31) up to Galton (1976: 9 and 285): all of them insist on the temporal content of both aspect and tense, although the basic idea of the common ’substance’ of the two categories in question is far from being identical in various systems. As regards the present study, it sets aside these more or less speculative approaches to the general relation between aspect and tense in order to concentrate on a concrete case of their functional interference. It is a typological and comparative attempt to demon- strate the syntactic structure of the temporal when-clause in its capacity as a general aspect test on material of several well-known languages and language groups: Ancient Greek, Latin, Romance, English, German and Slavic; isolated examples are given from Modern Greek and Hungarian. The application of such a model to some different linguistic systems has a double purpose: firstly, to emphasize the importance of verbal aspect among linguistic means by which in various languages the category of so-called ’relative time’ is expressed and, secondly, to investigate aspectual values of the verb and/or its forms in the same function in the languages taken here into account. Further we shall see that relative time and aspect, as nowadays is more and more pointed out, are two verbal categories that in the domain of syntax greatly overlap.
