I am going to play cricket.
I am not going to play cricket.
Are you going to play cricket?
Yes, I am./ No, I'm not.
1. What are you going to play?
I'm going to play cricket.
2. What are you going to do?
I'm going to play cricket.
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All the sentences are correct, aren't they?
By the way, which question is suitable for the answer? #1 or #2?
All of the sentences are correct. :-)
Both questions are suitable for the answer.
Number 1 assumes that you're going to play a sport. Number 2 is asking what you plan to do (go to the movies, study, play cricket, etc.).
GLAD TO SEE MRS SUE HERE ESPECIALLY ABOUT HEARING HER PASSING AWAY ;(
Yes, all the sentences are grammatically correct.
The suitable question for the answer would be #1: "What are you going to play?"
In the context given, the person is stating their intention to play cricket. Therefore, the most appropriate question to elicit that specific answer would be asking about what they are going to play.