1 has different meanings.

"Happiness" is an emotion, and "happiness" is an action.

For example:

Eat, drink and be merry. Eat, drink and be merry.

Britain and America are different.

British people prefer to say "Merry Christmas"; Because this is what the queen said in her Christmas speech:

The royal family adopted "Merry Christmas" as their preferred greeting, and others also noticed it.

Extended data:

Some people think that this day is chosen to celebrate Christmas because Christians believe that Jesus is the just and eternal sun. After the middle of the 5th century, Christmas, as an important festival, became a tradition of the church and gradually spread among the eastern and western churches. Due to the different calendars used, the specific dates and forms of activities held by various sects are also different.

Christmas customs mainly spread to Asia in the middle of19th century, and both Japan and South Korea were influenced by Christmas culture. Nowadays, it has become a common custom in the west to exchange gifts and hold banquets with Santa Claus and Christmas tree to add festive atmosphere. Christmas has also become a public holiday in the western world and many other regions.