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'.

Sentence 1:Artists ' impression of Giotto , the European Space Agency 's first interplanetary mission , launched in July 1985 . Sentence 2:nan
SINGLE_APPOSITION

Sentence 1:Charlie thinks that Nancy would leave the Osbornes house when Darren lies about it but he is told that she wo n't leave . Sentence 2:nan
SINGLE_S_COORD_ANAPHORA

Sentence 1:The HK51 has no real standards but is usually a cut down and modified G3A3 or its semi-automatic clones the HK41 and HK91 and modified to take MP5 furniture and accessories . Sentence 2:nan

SINGLE_S_COORD_ANAPHORA