7.2 The Clause as CP
This leaves main clauses. As pointed out in (11b), these never have overt complementisers. However, given that covert complementisers seem to be a possibility it is reasonable to ask whether main clauses are CPs which have an obligatory covert complementiser, or whether they are just IPs with no space for a complementiser. The issue is complicated unfortunately. On the one hand, there are some main clauses that have to be argued to be CPs, as we shall see a little later. Thus, on general grounds it seems reasonable to assume that all clauses are CPs. Moreover, if the role of the complementiser is to indicate the force of a sentence, and main clauses without complementisers have a force interpretation, then it might be argued that there must be a complementiser to provide this aspect of clausal semantics. On the other hand, most linguists accept that ‘exceptional clauses’ lack complementisers and these also have a force interpretation and so it seems that there is a way for this to be introduced in the absence of a complementiser, which undermines the argument that main clauses must have complementisers because they have a force interpretation.
7.2 The Clause as CP
If we assume that main clauses are CPs we need an explanation as to why their complementisers are obligatorily covert. But if we assume that main clauses are merely IPs, we must account for why the CP is obligatorily banned. All in all then, it is hard to decide on the issue. In this book, we will take the fairly standard view that all clauses are CP (except for the exceptions) and hence we assume that main clauses have obligatorily covert complementisers by a general principle.
So far, I have remained uncommitted about the status of the clause that contains PRO: is it a CP or is it an IP? Under both assumptions that PRO cannot sit in Case positions or that it can only sit in Null Case positions we have to ensure that the place where it can be found is not assigned a full Case from an element outside the clause. We have seen that as PRO cannot be the subject of an exceptional clause it must be assumed that this is not possible. One way to ensure that nothing else can assign Case to the place occupied by PRO is to assume that it is protected by a CP. Recall that a governor can govern up to a CP, but not through it as CP acts as a barrier to government. For this reason then, we will assume that all clauses containing a PRO subject are CPs and not IPs.
In this chapter we have dealt with a number of phenomena concerning non-finite clauses in English. On the whole, the interesting aspect of these constructions concerns their subjects. We have seen various possibilities for empty subjects in non-finite clauses, as with raising and control structures, and also exceptional accusative subjects in other constructions as with exceptional and small clauses. The gerund offers problems for analysis all of its own. By and large, we have offered analyses for all these structures, but have left many issues undiscussed and have ignored many alternative analyses. We might hope that this book has interested the reader sufficiently for them to follow up what has been left out here in further reading and research.