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'.
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Question: Sentence 1:Mallory and Bullock suggested names for the many topographical features they discovered and these were endorsed by the expedition and passed to Charles Bell , Britain 's special ambassador to Lhasa , for approval . Sentence 2:nan

Answer: SINGLE_APPOSITION


Question: Sentence 1:This particular crane was unrecognized at first because it was not native to this region . Sentence 2:nan

Answer: SINGLE_CONN_INNER


Question: Sentence 1:Wayne Barrett ( July 11 , 1945 -- January 19 , 2017 ) was an American journalist . Sentence 2:He was an investigative reporter and senior editor for The Village Voice for 37 years .

Answer:
PAIR_ANAPHORA