get line break right, clarify NIL usage

README.md

@@ -6,7 +6,7 @@ language_creators:
 languages:
 - en
 licenses:
-- other
+- cc-by-4.0
 multilinguality:
 - monolingual
 size_categories:
@@ -73,9 +73,9 @@ The file is tab separated, in CoNLL format, with line breaks between tweets.
 
 * Data preserves the tokenisation used in the Ritter datasets.
 * PoS labels are not present for all tweets, but where they could be found in the Ritter data, they're given. 
-* In cases where a URI could not be agreed, or was not present in
+* In cases where a URI could not be agreed, or was not present in DBpedia, the linking URI is `NIL`.
 
-DBpedia, there is a NIL. See the paper for a full description of the methodology.
+See the paper for a full description of the methodology.
 
 
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