Update README.md

README.md

@@ -90,8 +90,8 @@ For each instance, there is a document name representing the name of the documen
 - *ner-tags*: a list of string representing the annotation for each word.
 
 The allowed **ner-tags** are: 
-  - "O": 
-  - "B-Actor",
+  - **O**: An O tag indicates that a token belongs to no chunk.
+  - **B-Actor**: This tag indicates the beginning of an *Actor* chunk.
   - "I-Actor",
   - "B-Activity",
   - "I-Activity",