TASK DEFINITION: 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'.
PROBLEM: Sentence 1:Lulu notices this , so she plans to get to Mamoru after he leaves the planetarium , but Amu sees her . Sentence 2:nan

SOLUTION: SINGLE_S_COORD

PROBLEM: Sentence 1:Robert M. Ricketts developed the Utility arch in 1950s and it is considered to be an integral part of the Bioprogressive Therapy in Orthodontics . Sentence 2:nan

SOLUTION: SINGLE_S_COORD_ANAPHORA

PROBLEM: Sentence 1:Lacunae are distinct from loopholes , in which a law exists but which can be circumvented legally due to an unforeseen or unintended inadequacy in said law . Sentence 2:nan

SOLUTION:
SINGLE_S_COORD