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: Adam can't leave work here until Bob arrives to replace him. If Bob had  left home for work on time, he would be gone by this time.
 Question: Why does the 'he' refer to adam?
[EX A]: Because Adam can't leave work here until Bob arrives to replace him. If Bob had left home for work on time, he would be gone by this time.

[EX Q]: Sentence: The man couldn't lift his son because he was so weak.
 Question: Why does the 'he' refer to the man?
[EX A]: Because The man couldn't lift, why? Because he was weak.

[EX Q]: Sentence: Archaeologists have concluded that humans lived in Laputa 20,000 years ago. They hunted for evidence on the river banks.
 Question: Why does the 'They' refer to archaeologists?
[EX A]:
Because The archaeologists are the one that would be hunting for evidence.