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:Duncan MacDuff later married Mary , the niece of King Edward , and threw in his lot against the Bruce . Sentence 2:nan
Example Output: SINGLE_APPOSITION

Example Input: Sentence 1:In 1957 he even advocated in talks with Israeli officials that Arab Christians in Israel be drafted for military service . Sentence 2:However , his suggestions were unpopular with both the Israeli government and Israeli Arab political leaders .
Example Output: PAIR_CONN_ANAPHORA

Example Input: Sentence 1:The Fairy , whom David met in the army , and who was later discharged for being gay . Sentence 2:nan
Example Output:
SINGLE_RELATIVE