Incorrect and Correct Sentences

Incorrect and Correct Sentences :

Incorrect Sentence :

Is it your happy birthday today?

Correct Sentence :

Is it your birthday today?

'Birthday' refers to an event/occasion, while happy describes its nature.

So, whereas, while wishing someone one would say/write 'happy birthday', while referring to the event/occasion, one just uses the word 'birthday'.

Moreover, one needs to keep in mind that while wishing a person 'happy birthday' that the birthday should be happy is a wish, but one would be incorrect to refer to a birthday as essentially happy (i.e. it is your happy birthday), as it may not necessarily be so as for various reasons one's birthday may prove to be a sad day.

Incorrect and Correct Sentences