at least part of speech, grammatical number and gender, and so forth. In addition, section 3.2.3 observed that a lexical
ite mcan place a constraint on its syntactic environ ment; for instance a verb may be specified as transitive. Such a
constraint is called a subcategorization feature; we will see in section6.6how these are specified.
Among lexical formation rules we mightalso include principles of morphosyntax, whichmake it possiblefor words to
haveinternal syntactic structure.For instance, the wordperturbationis built fro mthe verbperturb, whichis converted to
a noun by attaching the ending -ation. It is common to analyze words like this in terms of a tree structure altogether
parallel to syntactic tree structures, except that the trees are inside of a word, as in (18a). Moreover, the trees can be
hierarchical, as in (18b).
The lexical formation rules must thus include tree fragments from which such structures can be built.
Turning to phonology, an item's phonological structure determines how it is pronounced. The formation rules for
lexical phonological structure have to specify the range of possible pronunciations for words in the language: the
inventory of phonological segments and how they combine into syllables and larger units. To cite a well-known
example,blikis a possible word of Englishbutbnikis not, because the syllabicformation rules for English permit the
onset clusterbl- but notbn- (eventhoughbn- is pronounceableand is a possibleonsetclusterinsomeother languages).
As illustrated in Fig. 1.2, phonological segments themselves have a systematic decomposition into features; the
possibilities for such decomposition are stated in terms of formation rules parallel to those for syntactic categories
such as (6).
An item's lexical semantic/conceptual structureis also conceivedof(inmostapproaches) as combinatorial. And again,
the lexical formation rules must specify the available repertoire of more basic units and how they are combined. We
return to this issue in Chapters 9–11.
The reader may have already detected hints that lexical formation rules are really very similar in format to phrasal
formation rules. And indeed this is the case, as we will bring out more clearly in Chapter 6.