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.

[EX Q]: Sentence: Fred is the only man still alive who remembers my great-grandfather. He is a remarkable man.
 Question: Why does the 'He' refer to fred?
[EX A]: Because "is" is present tense and indicates he is still alive.

[EX Q]: Sentence: John couldn't see the stage with Billy in front of him because he is so tall.
 Question: Why does the 'he' refer to billy?
[EX A]: Because Billy in front of him because he is so talJohn couldn't see the stage.

[EX Q]: Sentence: I was trying to open the lock with the key, but someone had filled the  keyhole with chewing gum, and I couldn't get it in.
 Question: Why does the 'it' refer to the key?
[EX A]:
Because The keyhole hole already had chewing gum in it. They tried to put the key in, but couldn't.