tokens: As for question 2 , you could go about using a canvas , but it would be quite difficult to use only a canvas , but possibly a combination of a canvas and a set of text views could work .
ner_tags: O O O O O O O O O O O B-Class O O O O O O O O O O O B-Class O O O O O O O B-Class O O O O B-Class I-Class O O O