Question: Marriott rewards frequent travelers with points for free stays, but they are also enticed by other reward programs from other hotels.
Based on this sentence, who is they?

Answer: frequent travelers

Question: The professor grading the student's paper said that he loved it.
Based on this sentence, who is he?

Answer: The professor

Question: Western Digital may disappoint their shareholders this season since they have slowed down production in their Thailand factories due to flooding.
Based on this sentence, who is they?

Answer: Western Digital

Question: A series of injections are used to battle a type of cancer in patients, but they do not always provide a hundred percent success rate.
Based on this sentence, who is they?

Answer:
A series of injections