The wh-trace relation seems the most interesting one because it shows both how general and powerful the mechanism is and how restrictive the rules should be to account for the data. At least the data show in (21) should be accounted for.
In the GB framework (e.g. Chomsky 1981), wh-movement is seen as an instance of the transformation 'move alpha', which respects the subjacency principle. The subjacency principle claims that no rule can relate X and Y in the following structure (22):
(22) ..X..[...[.Y..]..] .. a b where a, b bounding nodes (23) who [ .. [t [Bill told me [t [Susan saw t | s ||s ||s | |_________||_______________||___________|For English, S and NP are assumed to be bounding nodes. Wh-movement takes place cyclically via the comp-positions of the intermediate clauses, leaving behind traces (the so-called comp-to-comp movement). As such, it does not cross more than one bounding node at a time in a structure like (23).
Our discussion of wh-movement in the next section is
in accordance with the
comp-to-comp movement. Although other approaches, such as direct
movement, are feasible too, we will adhere to the comp-to-comp
approach. Data from Spanish (Torrego 1984) also seem to support the
preference for actual movement from complementizer to complementizer.
(24) Que [ dice Juan [ que [ creian los dos [ que
[ habia pensado Pedro [ que [ habia aplazado
el grupo [ el grupo habia aplazado
What says John that thought the two that
believed Peter had postponed the group ;
that the group had postponed
According to Torrego, inversion is obligatory in all clauses except
the lowest. In the lowest clause, inversion is optional. The GB
theory accounts for this by claiming that for Spanish S-bar, instead
of S, is the bounding node. This predicts that movement in the lowest
cycle can take place in two ways as shown in (25).
Neither of the two violates subjacency. Assuming that a wh-constituent, or its trace, in comp triggers inversion, the variation in Spanish word-order in the lowest cycle is accounted for.
We will return to these data in the next section. We will argue that
these data can be handled by the MiMo-mechanism as well, given the
correct rules for the binding of complementizers.