用英语写invitation的作文怎么写

Dear Mr.Smith,
You are invited to attend a hike to the Great Wall on Friday,November 17th. The coach will leave at 7 o'clock. Your family and friends are welcome,too.
We would feel honored if you can join us for the wonderful trip.

Dear Mr.Smith,
We have pleasure in inviting you to our annual conference. This year it will be taking place at the University of Nottingham, from 20 to 24 August.
We enclose details of the conference, accommodation arrangements and a business activity program.
Last year you gave a very interesting talk on the subject of "Academic Standards and Expectations". We would be very grateful if you would consider giving us an update on this .
We would appreciate it if you could confirm your participation at your earliest convenience.
Your sincerely,
XXX