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'.

Ex Input:
Sentence 1:A space charge develops a potential that slows the carriers down . Sentence 2:For example , an electron approaching a cloud of other electrons will slow down due to the repulsive force .

Ex Output:
PAIR_CONN


Ex Input:
Sentence 1:U.S. submarines participated in the majority of naval battles in the Pacific theatre , but the submarines were most decisive in their blockade of Japan , for which Japan was dependent on its sea transport to provide resources for its war effort . Sentence 2:nan

Ex Output:
SINGLE_S_COORD_ANAPHORA


Ex Input:
Sentence 1:He had been my colleague in the old Nigerian Army , although a junior colleague . Sentence 2:nan

Ex Output:

SINGLE_CONN_INNER