Answer: question mark
tejas asks: Should the sentence "Are you really sure you want to do that or would you rather live another day" end with with a period or a question mark?
Punctuation marks are cues to the reader as to how the text should sound. Commas indicate pauses, exclamation points indicate loudness or excitement, and question marks indicate the rise or fall of voice that comes with a question.
When you speak a true question, your voice will rise or fall in a way that it won't with a declarative sentence. This should be your guide, rather than where the verb is placed, or whether there is a who/what/when/where/how/why involved.
There are phrases that have been written grammatically as a question, but are actually statements--orders, and some rhetorical questions.
General Hammond glared at the Goa'uld SG-1 brought back through the gate. "Colonel, would you please bring our 'guest' to the nearest holding cell."
Jack took in the Jaffa surrounding them, and commented wryly, "Well, isn't this a charming welcome party."
And there are phrases that have been written grammatically as a statement, but are actually questions.
Daniel noticed the Budge on the shelf, and winced. "You're my new Egyptologist? Great."
In all the above cases, it's the punctuation that tells you how the speakers' words sound.
For tejas's specific question, I can hear it in my head as:
Are you really sure you want to do that, or would you rather live another day?
or
Are you really sure you want to do that? Or would you rather live another day?
But even with the most wry or threatening delivery, I can't hear it as a declarative sentence.
Punctuation marks are cues to the reader as to how the text should sound. Commas indicate pauses, exclamation points indicate loudness or excitement, and question marks indicate the rise or fall of voice that comes with a question.
When you speak a true question, your voice will rise or fall in a way that it won't with a declarative sentence. This should be your guide, rather than where the verb is placed, or whether there is a who/what/when/where/how/why involved.
There are phrases that have been written grammatically as a question, but are actually statements--orders, and some rhetorical questions.
General Hammond glared at the Goa'uld SG-1 brought back through the gate. "Colonel, would you please bring our 'guest' to the nearest holding cell."
Jack took in the Jaffa surrounding them, and commented wryly, "Well, isn't this a charming welcome party."
And there are phrases that have been written grammatically as a statement, but are actually questions.
Daniel noticed the Budge on the shelf, and winced. "You're my new Egyptologist? Great."
In all the above cases, it's the punctuation that tells you how the speakers' words sound.
For tejas's specific question, I can hear it in my head as:
Are you really sure you want to do that, or would you rather live another day?
or
Are you really sure you want to do that? Or would you rather live another day?
But even with the most wry or threatening delivery, I can't hear it as a declarative sentence.