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: The trophy doesn't fit into the brown suitcase because it is too large.
 Question: Why does the 'it' refer to the trophy?
[EX A]: Because The trophy was to be carried inside the suitcase, but wouldn't fir.

[EX Q]: Sentence: Frank was upset with Tom because the toaster he had sold him didn't work.
 Question: Why does the 'he' refer to tom?
[EX A]: Because he upset due to toaster sold.

[EX Q]: Sentence: Tom threw his schoolbag down to Ray after he reached the top of the stairs.
 Question: Why does the 'he' refer to tom?
[EX A]:
Because Tom threw his bag down, so he would be at the top of the stairs.