想約人食飯,英文會點樣講架?

John's birthday is coming! Will you be free to have lunch with us on Satuday from 1pm to 2pm? If you are ok, please reply me! Thanks! :)

The coming Saturday is our coleague John's birthday, we would like to invite you for lunch together at 1.00-2.00pm that day. Kindly reply by return email, thank you.

hi hi

Just want to say that John's birthday is on Saturday. I will invite him to take a lunch with me on that special date. Do you have an interest to join us? If so, please reply me ASAP.

Bye Bye

yr name

You can try the following:
Hello everyone,
I am setting up a birthday party for John on Sat. from 1 to 2 pm at xxxxx, RSVP, thank you and hope to see you there.

Regards,
XXXX
You can use birthday party or lunch gathering
RSVP means reply to the sender, let the sender know you are coming or not. Or you can use "Please send me an reply e-mail"

Dear XXX,

For celebrating John's birthday, I have appointed him to have lunch at 13:00-14:00 on this Saturday. Would you like to join us?? Please reply me soon.

Thanks & regards,
(your name)