e.g., "name", "type of", "called" Comparison clues e.g., "similar", "differ", "relate" Intersection clues superlative ADJ, ordinal ADJ, relative clause Topic Itself clues e.g., "show", "picture", "map"  answer (which is similar to our Focus).
our Focus decision tree includes additional attributes in its second split (these attributes are added by dprog because they improve predictive performance on the training data).