Theoretical Aspects of Movement(61) S
DP VP
Mary VP PP
met Mark in the park
After the movement, the structure will look like this:
(62) S
PP S
in the park DP VP
Mary VP -
met Mark
We call the structure before movement takes place, a D-structure and the post-
movement structure an S-structure. The ‘D’ and the ‘S’ originally stood for deep and
surface, reflecting the fact that S-structures represent an ordering of the elements
which is closer to that which holds in the externalisation of the sentence (its
pronunciation, or whatever) while D-structures represent an abstract level of
description more deeply embedded in the analysis. However, the words deep and
surface have unfortunate connotations which may lead to misunderstanding. Deep, for
example, can be taken to mean ‘meaningful’ or ‘ponderous’, while surface can mean
‘superficial’ or ‘apparent’. It would be wrong however to come to the conclusion that
deep-structure is somehow more important or that surface-structure is irrelevant. These
terms should be taken simply as referring to the two levels of the description of a
sentence and neither one nor the other is any more important than the other. This is
why the more neutral terms D-structure and S-structure are used and we will follow
this tradition.
2.2.1 D-structure and Theta Theory
Let us consider the nature of D- and S-structure a little more closely. An obvious
question is why it is that some elements start off in one position and then move to
another. To answer this question we have to ask about why elements occupy the
positions they do at any level of description. This is a matter of distribution: there are
grammatical principles which determine the range of possible positions of categories
of certain types. X-bar principles obviously have a large role to play in this,
determining head, complement, specifier and adjunction positions. But as both D- and
S-structures conform to X-bar principles, this clearly is not what differentiates the two.
Obviously there must be other grammatical principles holding at D-structure which are
not applicable at S-structure and vice versa.
A D-structure principle may then require a constituent X to occupy a certain
position and an S-structure principle may require X to occupy a certain position, and if