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.

Input: Consider Input: Sentence: The Albanians first appear in the historical record in Byzantine sources of the late 11th century.
Question: For how long did the Byzantines log historical records?

Output: Yes.

Input: Consider Input: Sentence: You can see examples of people with gravitational potential energy in 1.5 Figure below.
Question: What will a typical person do after reviewing the example?

Output: Yes.

Input: Consider Input: Sentence: Our investigation has uncovered no credible evidence that any person in the United States gave the hijackers substantial financial assistance.
Question: How long did the investigation span?
Output: Yes.