[Elements as they are added one by one to form a sentence progressively limit the semantic range of all that has preceded. This causes beginning elements to have a wider semantic range than elements toward the end. The concept of linear modification thus developed knits together a number of otherwise heterogeneous manifestations of sentence order in English, and provides a plausible theory of adjective position.]
The linear geometry of the sentence imposes certain relationships upon the elements that compose it. These relationships are conveniently expressed as dichotomies. Two dichotomies are, figuratively, spatial: they are contiguous versus separate (A is next to B or is distant from B) and within versus without (A is contained within B or is outside B). Two dichotomies are temporal : first versus last and before versus after. While it does not follow that any of these pairs necessarily has linguistic importance, given their location at the very foundation of sentence structure it would be strange if they had not been seized upon for some use in communication. I think it can be shown that all of them have, probably in all languages, though I am concerned here only with the last two, the temporal dichotomies, and even with these, only in two languages.