TASK DEFINITION: In this task, you are given two sentences in the English language and your task is to classify them into one of their discourse types. A discourse type is an indicator to classify the given two sentences on the basis of a co-text as well as a relevant context. There are 13 discourse types in total which are 'SINGLE_S_COORD', 'SINGLE_CATAPHORA', 'SINGLE_CONN_INNER', 'SINGLE_APPOSITION', 'SINGLE_VP_COORD', 'SINGLE_CONN_START', 'PAIR_ANAPHORA', 'PAIR_CONN', 'SINGLE_RELATIVE', 'SINGLE_CONN_INNER_ANAPHORA', 'SINGLE_S_COORD_ANAPHORA', 'PAIR_CONN_ANAPHORA' and 'PAIR_NONE'.
PROBLEM: Sentence 1:David Williams , the sole survivor of the trio that captured Major John Andre , died in 1831 . Sentence 2:nan

SOLUTION: SINGLE_APPOSITION

PROBLEM: Sentence 1:Visiting Tom 's grave , Alice finds a note left by Doug which reveals the killer to be Alice 's friend Marlena Evans . Sentence 2:nan

SOLUTION: SINGLE_CATAPHORA

PROBLEM: Sentence 1:Adults are on wing year - round , although they are scarcer in the dry season . Sentence 2:nan

SOLUTION:
SINGLE_CONN_INNER_ANAPHORA