instruction:
In this task you need to give reasons to justify the pronoun coreference relations. Each of the provided inputs contains a sentence with a target pronoun and a question about how to justify the coreference between a noun phrase and the target pronoun. Good practices involve the discussion about how the descriptions attached to the targeted pronoun relate to the noun phrase candidate in the question. The reasoning could come from one or multiple following knowledge types about commonsense: First: 'Property', the knowledge about property of objects (e.g., ice is cold). Second: 'Object', the knowledge about objects (e.g., cats have ears). Third: 'Eventuality', the knowledge about eventuality (e.g., 'wake up' happens before 'open eyes'). Forth: 'Spatial', the knowledge about spatial position (e.g., object at the back can be blocked). Fifth: 'Quantity', the knowledge about numbers (e.g., 2 is smaller than 10). Sixth: all other knowledge if above ones are not suitable. Write the sentence in natural language.
question:
Sentence: I poured water from the bottle into the cup until it was full.
 Question: Why does the 'it' refer to the cup?
answer:
Because cup gets water. So it gets full.


question:
Sentence: John couldn't see the stage with Billy in front of him because he is so short.
 Question: Why does the 'he' refer to john?
answer:
Because John had a taller obstacle.


question:
Sentence: Madonna fired her trainer because she slept with her boyfriend.
 Question: Why does the 'she' refer to the trainer?
answer:

Because The trainer was fired; she would not be expected to sleep with the boyfriend therefore was fired.