How nice to hear from you again.
Let me tell you something about the activity.
I’m glad to have received your letter of Apr. 9th.
I’m pleased to hear that you’re coming to China for a visit.
I’m writing to thank you for your help during my stay in America. 结尾部分：
With best wishes.
I’m looking forward to your reply.
I’d appreciate it if you could reply earlier.
Ladies and gentlemen, May I have your attention, please? I have an announcement to make.
All the teachers and students are required to attend it.
Please take your notebooks and make notes.
Please listen carefully and we’ll have a discussion in groups. Please come on time and don’t be late.
Please come and join in it.