structures. It is called theCoordinate XPrule, where X is a variable identifying
any element, such as noun or verb, and P is phrase. Coordinating conjunctions
are designated by CC. This rule supplies two pieces of information. First, any
phrase can be conjoined to another phrase of the same form. For example, any
two noun phrases can be linked using a coordinating conjunction. Second, the
two conjoined phrases function as a single unit that has the character of the indi-
vidual phrases. In other words, two noun phrases joined by a coordinating con-
junction function as a single noun phrase. The rule is sho wn as:
XPÆXP CC XPWe can see how the XP rule works in sentences 18 through 20. In 18, the sub-
ject isFred and Fritz,which exists as a single unit and can be represented by XP.
But the subject consists of the two noun phrases:FredandFritz.
- Fred and Fritz loved Cheerios.
The sentence grammar for 18 would be:SÆNP CC NP VPNPÆNVPÆV NPBecause language is inherently recursive, we can combine any number of
similar phrases in a single unit, as shown in sentence 19:
- Macarena danced, laughed, and sang at the party.
We would describe the grammatical structure of 19 as follows:SÆNP VPNPÆ(det) NVPÆVP VP CC VP PPPPÆprep NPCompound Sentences
The Coordinate XP rule also applies to entire clauses, giving us a way of de-
scribing the grammatical structure ofcompound sentences.A compound sen-
tence is one that has two independent clauses. The analysis proceeds in
PHRASE STRUCTURE GRAMMAR 117