Yes you do. You are directly addressing the person and should set their name off with a comma as in a full sentence (eg. "I hope you have a happy birthday, Amy.")
No.
happy belated birthday
because you are basically greeting the person by saying happy birthday.
Yes
Yes, a comma should be used after "happy Halloween" and before a proper noun. For example, "Happy Halloween, Sarah." This comma helps to separate the greeting from the person's name and adds clarity to the sentence.
The appropriate greeting for Easter is 'Happy Easter'. If one were to say Happy Birthday Jesus, at Christmas, they could say Christ is Risen at Easter.
No a greeting. A salutation is what you write at the end of a letter.
The main birthday greeting tends to be Happy Birthday. More elaborate greetings can take the form of poems or songs. Birthday Messages is a website that can provide inspiration for any birthday situation.
exclamation poi nt. It should be-- Hi!
"Shengrikuaile" is a greeting in Chinese that means "Happy Birthday" when translated to English. It is often used to wish someone a happy and joyous birthday celebration.
Since Jehovah's Witnesses do not celebrate birthdays, you would use the same greeting that you do any other day of the week.
No you shouldn't because it's a phrase spoken altogether
You can wish people happy birthday in many ways. Nowadays people wish each other happy birthday on facebook, send greeting cards to one another, and also exchange gifts.