All three questions mean the same thing.
=)
1. What are you going to do for your winter vacation?
2. I'm planning to go on a trip to Thailand with my family.
3. What are you going to do on your winter vacation?
4. What are you going to do during your winter vacation?
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Does #1 mean #3 or #4?
2 answers
1, 3, and 4 mean the same thing.