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'.

Example Input: Sentence 1:Scott received his B.S. degree from Massachusetts Institute of Technology and graduated with a J.D. from the University of California , Los Angeles . Sentence 2:He has taught as a law professor at Southwestern Law School .
Example Output: PAIR_ANAPHORA

Example Input: Sentence 1:Although rainfall is evenly spread throughout the year , it is more common in spring ( April -- May ) and autumn ( September -- November ) . Sentence 2:nan
Example Output: SINGLE_CONN_START

Example Input: Sentence 1:An additional system , GJ 758 , was imaged in November 2009 , by a team using the HiCIAO instrument of the Subaru Telescope , but it was a brown dwarf . Sentence 2:nan
Example Output:
SINGLE_S_COORD_ANAPHORA