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.
Example: Sentence: Jack played basketball after school, after which he was very tired. 
Question: How long did Jack play basketball?
Example solution: Yes.
Example explanation: All entities are in appropriate position and the question makes sense, so its grammatically and logically correct.

Problem: Sentence: Dam Square was landlocked for the first time in its history. 
Question: How long was it not landlocked?

Solution: No.