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'.

Q: Sentence 1:The YouTube app , which had been a default app on iOS developed by Apple , was removed . Sentence 2:nan

A: SINGLE_RELATIVE
****
Q: Sentence 1:Ghinzani , who was also very lucky not to hit Martini , limped away from his broken Osella and Grand Prix racing having banged his ankle on the cars monocoque . Sentence 2:nan

A: SINGLE_RELATIVE
****
Q: Sentence 1:It originally aired on the Fox network in the United States on April 30 , 1995 . Sentence 2:In the episode , Bart is rushed to the hospital after eating a jagged metal Krusty - O and decides to sue Krusty the Clown .

A:
PAIR_NONE
****