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'.
One example: Sentence 1:Paladin Blake , CEO of Blake Aviation Security then warns the Fortune Hunters to leave Pacifica given Blake has a zeppelin containing an armada of fighters . Sentence 2:The Fortune Hunters however sabotage the zeppelin and destroy it , along with Nathan personally fighting Blake himself .
Solution is here: PAIR_CONN_ANAPHORA
Explanation: Given two sentences, they are correctly classified based on their discourse type which is 'PAIR_CONN_ANAPHORA' because there are two sentences that are connected and the words repeated at the beginning of successive clauses.

Now, solve this: Sentence 1:He and his many graduate students , post doctoral workers and colleagues have played a central role in elucidating mechanisms of development of behaviour and the brain . Sentence 2:nan
Solution:
SINGLE_S_COORD