Corpus-format-description.md

@@ -11,11 +11,12 @@ In short, a _cupt_ file contains split sentences, each represented with one toke
 Similarly to _PARSEME:MWE_, the information in the 11th column called _PARSEME-FR:MWE_ contains one of the following three options:
  1. an asterisk '*' for words that are not part of a MWE/NE and for multiword tokens (e.g. _2-3 du_)
  2. an underscore '_' if the MWE/NE annotation is unspecified or missing
- 3. a list of semicolon-separated **codes** if the current word is part of one or more MWEs/NEs. Codes are only assigned to the lexicalized components of a MWE/NE (see [Lexicalized components and open slots](http://parsemefr.lif.univ-mrs.fr/parseme-st-guidelines/1.1/?page=lexicalized) in the PARSEME annotation guidelines).
-    - If the current line contains the first lexicalized component of the MWE/NE in the sentence, the code consists of an **identifier** followed by a colon ':' and a **pos-category-criteria label**:
-      * the **identifier** of a MWE/NE is an integer (starting at 1), and is unique within the sentence.
-      * **pos-category-criteria labels** are strings corresponding to information about the MWE/NE. These labels are composed of three fields separated by a pipe '|' character (i.e. POS|CATEGORY|CRITERION1,CRITERION2...):
-          1. **POS** is a tag representing the part of speech of the whole MWE/NE. The tags were inferred automatically using heuristics, or defined manually for irregular constructions. **[MARIE add link to POS details here if relevant](XXX)**.
+ 3. a list of semicolon-separated **codes** if the current word is part of one or more MWEs/NEs. Codes are only assigned to the lexicalized components of a MWE/NE (see [Lexicalized components and open slots](http://parsemefr.lif.univ-mrs.fr/parseme-st-guidelines/1.1/?page=lexicalized) in the PARSEME annotation guidelines). 
+    - for all the components of a MWE/NE except the (linearly) first one, the code is simply an **identifier**:
+      * the identifier of a MWE/NE is an integer, greater or equal to 1, and is unique within the sentence: the only requirement for identifiers is that all the components of a MWE/NE must have codes starting by the same identifier and no other MWE/NE in the sentence use it. 
+    - for the (linearly) first component of a MWE/NE, the code consists of an identifier followed by a colon ':' and a **pos-category-criteria label**:
+      * **pos|category|criteria labels** provide information about the MWE/NE. These labels are composed of three fields separated by a pipe '|' character (i.e. POS|CATEGORY|CRITERION1,CRITERION2..., for instance  ADP|MWE|IRREG describes a MWE (not a NE), whose part of speech is ADP, and for which the criteria IRREG has been used):
+          1. **POS** is a tag representing the part of speech of the whole MWE/NE, or a "_" if the MWE was classified as regular. Please refer to the [page describing the heuristics used to classify MWEs as regular / irregular, and to assign the POS to irregular ones](reg-irreg-pos-heuristics) for details.
           2. **CATEGORY** is a tag corresponding to a category that depends on the type of entity being annotated. It contains a prefix and a suffix, separated by a dash.
               * The prefix of the tag indicates whether this is a MWE (EP for _expression polylexicale_) or a NE (EN for _entité nommée_). 
               * The suffix depends on the prefix as follows: