Subcategorization frames

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Subcategorization frames are sets of rules used to generate syntactic structures out of the base form.

Contents

What are subcategorization frames

The idea of a subcategorization frame is related to the concepts of valency and transitivity. Subcategorization frames are schemas that define the number and the type of specifiers, complements and adjuncts that a base form needs to constitute its corresponding maximal projection.

For instance, the noun "apple" does not require any adjunct, specifier or complement to form a noun phrase (as in "I love apples"). The fact that it is often combined with other forms to form more complex noun phrases (as in "the apple", "delicious apple", "apple from Argentina", etc) is rather accidental, and does not affect the fact the word does not need them to constitute the simplest maximal projection. The same happens to the forms "beautiful" and "now", which may project, alone, an adjective phrase and an adverbial phrase, respectively.

However, there are forms such as "give", "of", "and", "Netherlands" and "interested" that cannot project phrases without the help of other constituents. They require specifiers, complements or adjuncts to form a "minimal maximal projection". The verb "give", for instance, requires at least one specifier (the subject) and two objects (a direct and an indirect), even if, in several contexts, they are not explicit[1]. The same happens to "of", "and" and "interested", which always requires a complement to form a prepositional phrase, a complementizer phrase and an adjective phrase, respectively. The form "Netherlands", on the other hand, requires a specifier ("the") to project a noun phrase (I go to Netherlands).

A subcategorization frame is a syntactic device that describe these conditions, i.e., what is really necessary (the obligatory constituents) for a form to project its corresponding maximal projection.

When to use subcategorization frames

Subcategorization frames are used in case of valent words whose syntactic needs follow a general rule, i.e., whenever there can be stated a regular pattern for generating constituents linked to the base form, such as specifiers, complements and adjuncts.

When not to use subcategorization frames

Subcategorization frames are not used in case of avalent words or in case of irregular behaviour, which is described by subcategorization rules.

Reference

The subcategorization frames are referred as follows:

  • by its common name (such as "intransitive", "direct transitive"), in case of well-established reference;
  • by the rule itself, in case of single-rule frames;
  • by the most distinctive rule, if any; or
  • by a "leading form", i.e., a typical example (a prototype) representative of the whole category, otherwise.

There are two predefined frames in the UNLarium:

AVALENT
If the word has valency equal to 0, i.e., if it does not require any argument.
IRREGULAR
If the word requires an argument but does not follow any existing frame.

Syntax

Subcategorization frames are expressed by S-rules, a special formalism for representing the syntactic structure of phrases.

<SYNTACTIC ROLE>(<REQUIRED>);

Where:
<SYNTACTIC ROLE> is the syntactic role (VA, VC, VS, VH, etc) of the term required by the base form; and
<REQUIRED> is the term required by the base form to saturate its syntactic structure. It is normally a maximal projection (NP, VP, JP, AP, PP) or a lemma (between [ ]). In case of PP, the head of the prepositional phrase is always informed: PP([in]), for instance, indicates a prepositional phrase whose head is the preposition "in".
A subcategorization frame normally involves more than one syntactic rule.

Examples

Rules Description Examples
NS([the]); The noun phrase requires the article "the" as its specifier (NS) the United States, the Netherlands, the United Kingdom
VS(NP); The verbal phrase requires a noun phrase as a specifier (VS) (intransitive verbs) sleep, die, etc.
VS(NP)VC(NP); The verbal phrase requires a noun phrase as a specifier (VS) and a noun phrase as a complement (VC) (direct transitive verbs) make, read, write, etc
VS(NP)VC(PP([on])); The verbal phrase requires a noun phrase as a specifier (VS) and a prepositional phrase headed by "on" as a complement (VC)(indirect transitive verbs governing "on") depend, insist, operate
VS(NP)VC(NP)VC(PP([to])); The verbal phrase requires a noun phrase as a specifier (VS), a noun phrase as a complement (VC), and a prepositional phrase headed by "to" as a complement (VC)(ditransitive verbs) give

Notes

  1. In sentences such as "John was given a book" or "I gave the book", arguments are either undefined or omitted but they do exist and, when absent from the sentence, are provided by the context. See valency.
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