instruction:
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'.
question:
Sentence 1:Packing to leave , she receives a telegram from her husband saying that Stroh will explain the misunderstanding . Sentence 2:nan
answer:
SINGLE_CATAPHORA


question:
Sentence 1:Descriptions of registered cultivars . Sentence 2:Retrieved 2006 - 11 - 15 .
answer:
PAIR_NONE


question:
Sentence 1:A study in Finland found that peat , which is high in humic acid , when used as poultry litter it was quite effective in controlling ammonia . Sentence 2:nan
answer:

SINGLE_RELATIVE