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.