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|  | '''UNL sentences''', or UNL expressions, are sentences of UNL. They are hypergraphs made out of nodes ([[Universal Words]]) interlinked by binary semantic [[relations]] and modified by [[attributes]]. UNL sentences have been the basic unit of representation inside the UNL framework.
 |  | #REDIRECT [[UNL Sentence]] | 
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|  | == Syntax ==
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|  | According to the [[Specs|UNL Specs]], there are two different ways of representing UNL sentences: the table format and the list format. In the list format, UWs and relations are represented separately; in the table format, they constitute a single structure.
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|  |   |  | 
|  | === List Format ===
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|  | The syntax for UNL sentences in the list format is the following: 
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|  |   |  | 
|  | {|
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|  | |<UNL sentence>
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|  | |::=
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|  | |"[W]" <list of UWs> "[/W]" [ "[R]" <list of relations> "[/R]" ]
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|  | |-
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|  | |<list of UWs>
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|  | |::=
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|  | |<UW+attributes> [<UW+attributes>...]
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|  | |-
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|  | |<UW+attributes>
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|  | |::=
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|  | |<UW>{“:”<Scope-ID>}}[<attribute list>]”:”<UW-ID>
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|  | |-
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|  | |<list of relations>
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|  | |::=
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|  | |<binary relation>[<binary relation>...]
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|  | |-
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|  | |<binary relation>
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|  | |::=
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|  | |<source node><relation[":"<Scope-ID>]<target node>
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|  | |-
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|  | |<source node>
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|  | |::=
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|  | |<UW-ID>
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|  | |-
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|  | |<target node>
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|  | |::=
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|  | |<UW-ID>
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|  | |}
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|  |   |  | 
|  | === Table Format ===
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|  |   |  | 
|  | The syntax for UNL sentences in the table format is the following:
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|  |   |  | 
|  | {|
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|  | |<UNLsentence>
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|  | |::=
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|  | |<list of relations>
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|  | |-
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|  | |<list of relations>
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|  | |::=
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|  | |<binary relation>[<binary relation>...]
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|  | |-
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|  | |<binary relation>
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|  | |::=
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|  | |<relation> [“:”<Scope-ID>] “(“ <source node> , <target node> ")"
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|  | |-
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|  | |<source node>
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|  | |::=
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|  | |<UW+attributes>
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|  | |-
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|  | |<target node>
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|  | |::=
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|  | |<UW+attributes>
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|  | |-
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|  | |<UW+attributes>
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|  | |::=
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|  | |<UW>{“:”<Scope-ID>}}[<attribute list>]”:”<UW-ID>
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|  | |}
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|  |   |  | 
|  |   |  | 
|  | Where <br >
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|  | " and " indicate a predefined delimiter <br >
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|  | < and > indicate a non-terminal symbol <br >
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|  | { and } indicate a range <br >
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|  | [ and ]indicate an omissible part <br >
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|  | ... indicates more than 0 times repetition of the front part <br >
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|  | <nowiki>::= indicates the left part can be replaced by the right part </nowiki><br >
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