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 ?

Subcategorization frames are sets of subcategorization rules that apply for a wide range of cases, i.e., that are regular.

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.

For instance, many verbs in English take a NP as a specifier (subject) and another NP as complement (direct object). This syntactic behavior, described by the frame VS(NP)VC(NP);, can be assigned to many different verbs and, therefore, must be defined as a subcategorization frame.

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.

For instance, very few verbs, in English, admit more than two arguments, such as "to bet" in "I bet you ten pounds that they lose". This syntactic behavior, which can be described by the rule VS(NP)VC(PPR)VC(NP)VC(CH([that]));, as very specific, is likely to be defined as a subcategorization rule, to be created inside the dictionary, rather than as a subcategorization frame, created in the grammar.

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.

<HD SYNTACTIC ROLE>(<ARGUMENT>);

Where:
<HD SYNTACTIC ROLE> is a head-driven Syntactic role (VA, VC, VS, VH, etc) of the term required by the base form; and
<ARGUMENT> is the term required by the base form to saturate its syntactic structure, i.e., in order to form the simplest maximal projection (NP, VP, JP, AP, PP, DP).

Observations

  1. There must be as many syntactic roles as necessary arguments inside a subcategorization frame
    • VS(NP); (intransitive verbs)
    • VS(NP)VC(NP); (direct transitive verbs)
    • VS(NP)VC(NP)VC(NP); (a verb with two direct objects)
    • VS(NP)VC(NP)VC(NP)VC(NP); (a verb with three direct objects)
  2. The arguments must be represented by their corresponding maximal projection (NP,VP,etc.) or by a XH relation in case the argument is necessarily headed by a given word:
    • VS(NP)VC(NP); (verbs taking a NP as specifier and another NP as complement)
    • VS(NP)VC(PH([of])); (verbs taking a NP as specifier a PP introduced by [of] as a complement = PH([of]);)
  3. The arguments may have as many features as necessary, provided that they are necessary and represented according to the Tagset.
    • VS(NP,NOM); (verbs taking a NP in the nominative case (NOM) as specifier)
    • VS(NP,NOM)VC(NP,ACC); (verbs taking a NP in the nominative case as specifier and another NP in accusative case as complement)
    • VS(NP,PPR,NOM); (verbs taking a NP that is a personal pronoun (PPR) in the nominative case (NOM))
    Features of arguments may be omitted if they are default
    If the NP is always NOM in VS there is no need for VS(NP,NOM); the frame must be simply VS(NP);
  4. Maximal projections must explicitly indicate the value of the phrase when they are fixed.
    • NS(DP([the])); (the noun requires the DP "the", i.e., the whole DP is fixed and cannot be modified)
    compare with
    • NS(DH([the])); (the noun requires a DP headed by "the", i.e., the DP structure is variable, provided that it is headed by "the")
  5. Strings must be represented between "quotes" while headwords must be represented between [brackets].
    • VC(PH([of])); (the word "of" is supposed to be included in the dictionary and, therefore, must be represented as an [entry]
    • VC("to the lions"); (the expression "to the lions" is not supposed to be included in the dictionary and, therefore, must be represented as a "string"

Examples

Rules Description Examples
NS(DP([the])); The noun phrase requires the determiner phrase "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(PH([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(PH([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

Software