'declarative' questions and 'interrogative' questions (When to use which?)

Question

Declarative questions:

1. 'Boss' and 'Manager' can be used interchangeably?

2. She is going there tomorrow?

AND

Interrogative questions:

1. Can 'Boss' and 'Manager' be used interchangeably?

2. Is she going there tomorrow?

So my question is when to use the above type of questions (declarative) and when to use the latter ones (Interrogative)?

Although I used to use them both in any situation but some time ago a native speaker pointed out that you can't use both of them in any situation. But that person also said that he doesn't know the rules regarding this, and just 'know it'. So any ideas when to use which structure of question?

Answer 1

Ordinarily you use the 'declarative' only when the question is 'echoic' - that is, when you are asking for confirmation or clarification of what you have just heard, often explicitly echoing the language your interlocutor has employed. In most cases you will stress a specific term which you find incredible or did not hear clearly.

A: Janet's going to France next year!
B: She's going to France?
C: Janet's going to France? I thought it was Jessica.

And in these circumstances, where you are questioning what you have just heard, you will not use the ordinary interrogative form unless you stress such a term—otherwise your interlocutor is apt to respond “Weren’t you listening? Didn’t I just tell you that?”

A: Janet's going to France next year!
B: Is it France she's going to? not Spain?
C: Is it Janet who's going to France, or Jessica?

But if you are not responding to what has been said, if you're just asking for information, you will ordinarily use the interrogative form.

Answer 2

StoneyB's explanation is correct. If you are in doubt, use an "interrogative question".

If you, like, use "declarative questions" too much, people will think you are talking like a Valley Girl, or something. Valley Girls were, like, stereotypical early 1980s teenagers who, like, said "like" all the time. They were gossipy and excitable, so they asked, like, a ton of "declarative questions". You know, like they were in a movie or something?

Answer 3

Here is maybe a grey area.

I wrote a 'meet cute' scene where a man meets a woman by interrupting her singing to herself. They are bantering jovially, when he says...

"What's your name again? You aren't the real 'Chrissie Hynde', are you."

Now I did not use a ? after this, because the second statement is not really a question. Both parties know the answer, and don't expect an answer. It is more a statement designed to troll the woman just a little bit, and have some fun with her.

Now this might not be a true rhetorical question, but it feels right to treat this as a statement rather than a question, due to the intent of the speaker. But 'are you' is nearly always a question, so I am not sure I am doing this properly.

But 'are you?' (voice going up) would make it seem like the man is mocking her a bit too strongly, and pretending sarcastically to not know the answer. 'Are you.' (voice trailing down) allows her to skip answering and move forward, making the trolling just a bit more polite and playful.

So....grey area, I guess.