While using "whether" in qustioning sense, is it correct to use the sentence with question mark (?) at the end? Or we have to write without question mark. Please advise.
Whether Ann is guilty of murder?
Whether Ann is guilty of murder.
Which one of the two is correct?
The example you have is not a complete sentence, so I can't determine whether a question mark is required or not. By the way, whether is not a WH-word--at least not in Modern English, so it doesn't require a question mark.
Click on the link below to see how to use whether.
whether - Definitions from Dictionary.com