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:Matthias , who suffered from gout , could not walk and was carried in a litter after March 1489 . Sentence 2:nan
Example Output: SINGLE_RELATIVE

Example Input: Sentence 1:The limestone contains marine fossils including crinoids , brachiopods , gastropods , horn corals , and bryozoans . Sentence 2:However , most of the fossils are too small for the human eye to detect .
Example Output: PAIR_CONN

Example Input: Sentence 1:Deol continuously garners attention for his portrayal of complex characters on screen , and is vociferous in his support for parallel cinema in India . Sentence 2:He has often been labelled as a nonconformist or an unconventional actor by Indian media .
Example Output:
PAIR_ANAPHORA