I appreciate your help. One more time, I posted the questions concerning the use of prepositions. Would you check the questions? Thank you.
1. We ate turkey on Thanksgiving Day.
2. We ate turkey at Thanksgiving.
3. We ate turkey on Thanksgiving.
[What about these sentences? Which one is not used? Do we have to use 'at' or 'on' before 'Thanksgiving'?]
4. He will visit the place on Christmas Day.
5. He will visit the place at Christmas.
6. He will visit the place on Christmas.
[What about these sentences? Which one is not used? Do we have to use 'at' or 'on' before 'Christmas'?]
7. Ann will come to her uncle's on Easter Day.
8. Ann will come to her uncle's at Easter.
9. Ann will come to her uncle's on Easter.
[What about these sentences? Which one is not used? Do we have to use 'at' or 'on' before 'Easter'?]