This is fine.If you see any problems, can I have your comments? Thanks always.
1. You seemed to very upset because you were charged for drinks ,which you thought were for free.
2.The drinks were free but only between 7 and 8 p.m. as advertised. (You should have checked the time on the promotional ad one more time before you came to the restaurant)
3. Everyone at the bar enjoyed free drinks between 7 and 8 p.m.
Student or Learner