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.

[EX Q]: Sentence: For example, buy local produce at a farmers market, like the one in Figure 2.20.
Question: What happened after produce was bought at the farmers market?
[EX A]: Yes.

[EX Q]: Sentence: He loved spending time with him when he was younger, but he had moved last year.
Question: How long did the move take?
[EX A]: Yes.

[EX Q]: Sentence: In the end , they drive off , listening to the radio .
Question: Was the vehicle they were driving built before the trip started?
[EX A]:
No.