S-rule
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				S-rule (syntactic rule) is the formalism used for describing syntactic hierarchies and syntactic operations in the UNLarium framework.
When to use S-rules
S-rules are used for:
- creating compounds out of the base forms (such as "take">"take into account");
 - generating complex grammar structures (such as "love">"will love");
 - defining syntactic roles (such as "subject", "object", etc);
 - defining dependency relations (such as agreement);
 - defining the distribution (i.e., order and adjacency) of word forms; and
 - projecting syntactic structures out of the constituents.
 
When not to use S-rules
S-rules are not used for for affixation (prefixation, infixation, suffixation) or spelling changes, which are dealt by A-rules and Ph-rules, respectively.
Types of S-rules
There are four types of S-rules:
- Head extension extends a given head.
 - Specification creates a specifier (determiner) to the head;
 - Complementation creates a complement (object) to the head;
 - Adjunction creates an adjunct (modifier) to the head; and
 
Syntax
S-rules comply with the following syntax:
CONDITION := RELATION(HEAD; ARGUMENT);
Where
- CONDITION (optional) is a tag or list of tags, extracted from the UNDLF Tagset, or a relation or list relations, that indicates when the rule should be applied, and that it's to be omitted if always applied;
 - RELATION is the syntactic relation, extracted from the syntactic roles, between the head and its argument;
 - HEAD (optional) is the head of the syntactic structure, which is to be omitted when does not undergo any change;
 - ARGUMENT (optional in case of head-only relations) is the argument (the specifier, the complement or the adjunct) of head.
 
The HEAD and the ARGUMENT may be expressed as:
- a "string" (strings must come between parentheses);
 - a [lemma] (lemmas must come between square brackets);
 - a feature or a set of features, separated by comma, and extracted from the the UNDLF Tagset;
 - a phrase (NP, VP, PP, etc), extracted from the [syntactic roles];
 - a direction (">",">>","<","<<");
 - a variable (to be specified both in the left and in the right side of the rule by the syntax %name)
 - an action, to be performed through an A-rule
 
Examples
Examples of S-rules:
- word-formation
- VA("into account"); (add the string "into account" as the adjunct of the verb)
 
 - compound tenses:
- FUT:=IH([will]); (add the lemma "will" as the head of the inflectional phrase)
 
 - government
- VC(PP([in])); (the complement of the verb must be introduced by the preposition "in")
 
 - agreement
- VS(ANUM,APER); (the specifier of the verb assigns number (ANUM) and person (APER) to its head
 
 - distribution
- VA(>>); (the adjunct of the verb comes at the right side after a blank space)
 
 - projection
- VS(%head;%spec)VB(%head;%comp):=VP(VB(%head;%comp);%spec);