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:However , 2 + ions ( Be ) or even 1 + ( Li ) show some polarizing power because their sizes are so small . Sentence 2:nan

Answer: SINGLE_CONN_INNER_ANAPHORA


Question: Sentence 1:Nothing of Espadero 's music has remained in the repertoire , yet his later pieces -- allegedly his best output , albeit never printed - remain to be investigated . Sentence 2:nan

Answer: SINGLE_S_COORD_ANAPHORA


Question: Sentence 1:The drama is based on a popular comic by Kang Full that has already been turned into a movie , which tells the love story between the elderly , and is SBS Plus ' first feature - length drama to be produced in - house . Sentence 2:nan

Answer:
SINGLE_RELATIVE