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.

[Q]: Sentence: The scientists are studying three species of fish that have recently been found living in the Indian Ocean. They appeared two years ago.
 Question: Why does the 'They' refer to the fish?
[A]: Because The fish would  be the subject of the study and would have appeared to years ago.


[Q]: Sentence: Bob paid for Charlie's college education. He is very generous.
 Question: Why does the 'He' refer to bob?
[A]: Because He is very generous. Bob paid for Charlie's college education.


[Q]: Sentence: The man couldn't lift his son because he was so heavy.
 Question: Why does the 'he' refer to the son?
[A]:
Because The son is being lifted and would be the one that was too heavy to lift.