happy christmas eve is correct, which means happy Christmas Eve, but it is usually capitalized, that is, Happy Christmas Eve. Christmas Eve is Christmas Eve (December 24th), that is, Christmas Eve.

Example:

I wish? everyone? Christmas! ? Have? a? happy? Christmas? eve!

I wish you all a Christmas! Have a happy Christmas Eve!

christmas eve tradition:

1. Giving gifts to relatives and friends

This tradition originated from a legend: three wise men gave gifts to baby Jesus at Christmas. Every Christmas, friends and relatives, especially children, give gifts to each other, and the story of Santa Claus also comes from this tradition.

2. Bake Christmas cake

Christmas cake is an English tradition, which spread centuries ago. People used to drink plum porridge on Christmas Eve. As time goes by, people will also enjoy preserved fruits, honey and spicy foods, and then Christmas cakes will replace plum porridge. Christmas cake is baked with eggs, butter, dessert, fruit, etc. Nowadays, Christmas cake has become an indispensable part of Christmas menu.