6.2.2 Do-insertion

6.2.2 Do-insertion

The movement represented in (26a) appears to be grammatical whereas that in (26b) is ungrammatical. Again the difference between the two is that the grammatical movement is shorter. But if we want to use the HMC to account for the phenomena, it must be the case that the negative is a head as it is moving over this element that causes the problem. But, what kind of a head is the negative? It is situated between the inflectional element and the v/VP:

6.2.2 Do-insertion

Accepting this, we can account for the insertion of dummy do. The verb will not be able to move to inflection without violating the HMC. Apparently in English, the negative is not the sort of verbal element that can support tense and hence the only option available is to insert an auxiliary. As there is no aspectual morpheme to deem otherwise, the inserted auxiliary will be do:

7.3.3 Inversion

As we can see, a yes–no question involving a main verb moving to the C position is ungrammatical and instead of the main verb moving to C what happens is that the dummy auxiliary do is inserted into the tense position, and from there it moves to C, via I. Of course, this is readily accounted for if main verbs do not move to I, as is the standard assumption. If they are never in I they cannot move to C without violating the head movement constraint. But we argued that main verbs can move to I and so it is not readily apparent why they cannot move to C. We will put this issue to one side until we have discussed the facts about I-to-C movement more fully. For the time being, then, we will concentrate on I-to-C movement as it involves auxiliary verbs.

8.2.1 Raising

In this way, each clause is provided with a subject, the trace, and hence the EPP can be satisfied. The ungrammaticality of (63) demonstrates that when a subject raises, it cannot actually be moved too far. Looking at what is possible and what is not possible with such movements, there is something similar about the restriction to the restriction we have noted concerning head movement. Recall that he Head Movement Constraint demands that heads do not move over the top of other heads. It appears that the restriction on subject movement is that it cannot cross over the top of another subject. A general way to express both these restrictions is to claim that a moving element cannot move over the top of a like element. This principle, known as Relativized Minimality, was introduced by Rizzi (1990) as a way of accounting for locality conditions on movement. The following diagram might help to make clear how the principle works: