One possible version:
Hi, Dave, I’m sorry to inform you that there are two changes to the schedule for English Day. First, there will be a very important meeting after lunch in our school, so English Talk Show will be put off by 30 minutes. That is, it starts at 13:00 and ends at 14:30. Second, the place of English Corner will be changed from Playground to School Hall because the weather report says it’s going to rain that afternoon. Please come and join us on time. Li Ping
