A question that is free of any grammatical or logcal errors, should be labeled 'yes', otherwise it should be indicated as 'no'. A question is grammatically correct if all its entities i.e. nouns, verbs, adjectives, prepositions, pronouns, adverbs are at appropriate position. A question is logically correct if the semantic makes sense.
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Question: Sentence: Ratners's chairman, Gerald Ratner, said the deal remains of ""substantial benefit to Ratners."". 
Question: What time of day did he speak?

Answer: Yes.


Question: Sentence: Alexander II's death caused a great setback for the reform movement. 
Question: When did Alexander II die?

Answer: Yes.


Question: Sentence: At current rates of use, coal will last about 300 years. 
Question: How long has been coal used for industrial needs?

Answer:
No.


