You can say:
(1) I am going to the dinner tonight. (The dinner has been arranged)
If a potluck has been arranged, can you say:
(2) I am going to the potluck today.
(3) I am going to join in the potluck today.
Are (2) and (3) grammatically correct? Thanks a lot.
(1) I've been invited to dinner tonight. No No
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
You can say (2) and (3) if the people you are talking to understand that by 'potluck' you mean an informal meal to which visitors take a random selection of miscellaneous food.