TASK DEFINITION: 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.
PROBLEM: Sentence: I clapped her shoulder to show I was not laughing at her. 
Question: What happened after they clapped her shoulder?

SOLUTION: Yes.

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

SOLUTION: Yes.

PROBLEM: Sentence: Our investigation has uncovered no credible evidence that any person in the United States gave the hijackers substantial financial assistance. 
Question: How often are investigations like this launched?

SOLUTION:
Yes.

