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:Arriving at New York City in December 1988 , he began coaching youth soccer teams : the Elmont Ravens girls ' team , the Brooklyn Patriots boys ' team , and the Gotham Girls Chargers team . Sentence 2:nan
Example Output: SINGLE_CATAPHORA

Example Input: Sentence 1:Since there are many potential gene targets , they continually utilize bioinformatics methods to winnow down and determine which are most relevant . Sentence 2:nan
Example Output: SINGLE_CONN_START

Example Input: Sentence 1:Following at the rear of the 12th ( Yorkshire ) Parachute Battalion , they arrived at Le Bas de Ranville . Sentence 2:nan
Example Output:
SINGLE_CATAPHORA