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: Jerry swims in circles until Tom's head has done a 360 , and is then grabbed again . 
Question: What happened before Jerry swam in circles?
[EX A]: Yes.

[EX Q]: Sentence: At this early stage in its history Japan was already (for the most part) only nominally ruled by the emperor. 
Question: How long did the Emperor rule Japan?
[EX A]: Yes.

[EX Q]: Sentence: There are now more protons than electrons inside the atom. 
Question: How long was the atom monitored?
[EX A]:
Yes.

