Basic English Syntax with Exercises

recursive rule

2.1.1 The building blocks of sentences

This rule defines sentences in terms of sentences and so the definition refers to what is being defined. A rule that does this is known as recursive, and recursive rules have exactly the property that we want to be able to define human languages. Recall from the discussion in Chapter 1, human languages are limitless and yet they must be defined by a finite set of rules as the human head can only store a finite amount of information. If I-languages are made up of recursive rules, then a finite set of these will be capable of defining an infinite number of expressions that make up an E-language.

3.1.5 Adjuncts

The final thing to note is that the adjunction rule is recursive: the same symbol appears on the left and the right of the rewrite arrow. Thus the rule tells us that an element of type Xn can be made up of two elements, one of which is an adjunct and the other is another Xn. Of course, this Xn may also contain another Xn, and so on indefinitely. In this way, any number of adjuncts may be added to a structure.

3.1.5.1 Adjunction to X-bar

The part of the structure containing the AP is recursive with an N' as the mother and an N' as one of the daughters. This means that there is room for more APs, as demonstrated by (36):

3.1.5.2 Adjunction to phrase

These clauses are not complements of the nouns, the nouns in (37) all being intransitive, and cannot be specifiers as they follow the head. Like AP adjuncts, they are recursive, demonstrating a clear property of an adjunct:

3.1.5.2 Adjunction to phrase

In this case it is the NP that is recursive, the top NP node contains the relative clause and another NP. This means that there is room for further relative clauses:

3.1.5.3 Adjunction to head

Given that the second noun is the head, it follows that the first element is an adjunct to the head. In principle, we should be able to get multiple head adjuncts by the same recursive process as we have noted with other adjuncts. However in practice it is not so common to find multiple compound nouns of this type. It is more common to find the adjunct itself being made up of a compound, which has a very different structure. Compare the following: