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:Yet his training was breached by another illness , hepatitis . Sentence 2:However , this did n't stop him ; a year later he was training again and taking the advance course in swimming , the competitive course , at age nine .

Answer: PAIR_CONN


Question: Sentence 1:Since the transition , it has been , however , extremely rare for a text to be written predominantly in classical Chinese , mainly because it lacks in words essential to describing modern life or expressing Western - originated concepts . Sentence 2:nan

Answer: SINGLE_CONN_INNER_ANAPHORA


Question: Sentence 1:Fox was initially employed at $500.00 per year by the US Navy as a clerk draftsman working under Naval Constructor Joshua Humphreys at Philadelphia Naval Shipyard . Sentence 2:Humphreys was the designer of the first Navy frigates .

Answer:
PAIR_ANAPHORA