No, it is not correct to say "one an." The correct phrase is "one and a half day" to refer to one full day and half of another day.
No, it is more correct to say, "What day is it today?"
Wednesday morning, it is correct to say I have not seen him for one day. Wednesday afternoon, or by working day end, it is correct to say I have not seen him for two days
You would say "Have a euphoric day".
It is correct, but you could also say:These daysNowadaysIn this day and age
The sentence structure is a bit awkward. It would be better to say, "Have a wonderful day ahead" or "I hope you have a wonderful day ahead."
It is correct to day "he divided the cake in half". The alternative is to add a word and say "he divided the cake into halves".
Either one is correct; the meaning is the same.
No, it is more correct to say, "What day is it today?"
Not quite. The word 'day' should be plural: There are thirty-one days.
Sure.
Wednesday morning, it is correct to say I have not seen him for one day. Wednesday afternoon, or by working day end, it is correct to say I have not seen him for two days
It is correct to say "such an exhausting day", and not 'Such an exhaustive day'.
Is it correct to say no one cares?
You would say "Have a euphoric day".
No.
It's all right with me :)
yes it's absolutely correct