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:Willamson , The Williamson Amplifier - A collection of articles reprinted from Wireless world , ( Reprint 1994 ) . Sentence 2:nan
Example Output: SINGLE_APPOSITION

Example Input: Sentence 1:Solomon , an attorney with a previous career in business , started as a health - care advocate in 1992 when her son was diagnosed with type 1 diabetes . Sentence 2:nan
Example Output: SINGLE_APPOSITION

Example Input: Sentence 1:The Carpathian Basin was more suitable for agriculture than large livestock grazing , and therefore increased steadily in the former weight . Sentence 2:nan
Example Output:
SINGLE_VP_COORD