If Im invited to an opening party for my work (a shop) with a partner, can it just be a friend?

Question

Does it have to be a partner partner? Or just a friend?

And how do I write an RSVP email?

Answer 1

Sure, it can be just a friend.  however if you are bringing someone of the same s*x, you need to subtley make it clear that you are not g*y,

For example, Meet my friend Pat, we have been friends since childhood. or We are on the same baseball team,  or I used to date Pat's sibling/  or whatever suits.

As for the e-mail,  just make it simple-  -- Just letting you know, that I will be  attending the party with a guest