Question: There is currently more work on coreference resolution than on chunking because it is a problem that is still far from being solved.
Based on this sentence, who is it?

Answer: coreference resolution

Question: Walmart has leaked pages of their Black Friday Ad to the users of the internet, but they will have many other ads to look at to choose from.
Based on this sentence, who is they?

Answer: the users of the internet

Question: Michael asked Jacob to dance because he felt sorry for him.
Based on this sentence, who is he?

Answer: Michael

Question: David hit Bill because Mary asked him to.
Based on this sentence, who is him?

Answer:
David