I've bundled up my comments into an answer of sorts. (ha, it looks worse than the comments - who chose these colours and fonts?)
In British English (or rather in Britain) I've certainly heard aren't we etc used in that way. Whether it is right/proper/by the rules/grammatical/whatever I have no idea .
One of us is wrong, aren't we?
It's got a question mark, ...
"He's too weak to walk"
Is he ? suggests that the person asking is doubting, or at least needing confirmation of the assertion.
Isn't he? suggests the person agrees with the assertion.
The point is, they have different meanings and should be used depending entirely upon whether or not the person asking agrees or not with the assertion.
In American Standard English, all of your example sentences sound awkward, bordering on wrong,1 but people will still understand the meaning. The natural way for me to express these statements would be without a question tag at all — here are two variations on each, differing in nuance:
Isn’t one of these balls blue?
Shouldn’t one of these balls be ...
The Chicago Manual of Style, 15th Edition (2003) has this entry under "Exclamation Point":
6.77 Exclamation rather than question. A question that is essentially an exclamation usually ends with an exclamation point.
How could you possibly believe that!
When will I ever learn!
If we take this guidance seriously, it seems to me, then for like ...
Wikipedia has an overarching approach:
Balanced vs unbalanced tags
English question tags exist in both positive and negative forms. When
there is no special emphasis, the rule of thumb often applies that a
positive sentence has a negative tag and vice versa. This form may
express confidence, or seek confirmation of the asker's opinion or
I don't normally answer my own questions, but in this case I feel compelled to do so. FumbleFingers' answer — the only answer this question has received* — while well-argued and not incorrect, feels like the answer of someone who is faced with a problem he recognizes but cannot solve, and so falls back on whatever has served in the past: in this case, the "...
As a native speaker of American English,
One of these balls is blue, aren't they?
sounds definitely wrong. My explanation for why it feels wrong is that the core of the subject is One, which is singular. The prepositional phrase of these balls doesn't change the grammatical number of the subject. Compare:
Isn't one of these balls blue?
= One of these ...
The grammatical version of your sentence is:
All the scheduled payments will be sent this night, won't they?
This question at the end of the statement is a question tag. It is used when the speaker wants to check that the statement is correct. In order to form it you use only the auxiliary verb (will in your case) with the subject of the verb in negative ...
I think you're right.
since the sentence expresses a negative meaning.
Nope, there is no negation operator in "He's too weak to walk."
On the other hand, a sentence like, "It hardly solves our problems, does it?" has a positive question tag because hardly acts as a negation operator here.
In simple usage, the question tag always mirrors the clause which makes the statement:
You shouldn't take sugar, should you?
You won't take sugar, will you?
Changing the question tag makes it into a statement and a supplementary question. Note the change in written punctuation, which may not be so obvious in speech.
You shouldn't take sugar; will ...
In the US we most commonly use right for that purpose:
She's pretty, right?
That movie sucked, right?
You're an extraterrestrial, right?
It's really raining out there, right?
Using yes in these instances would indicate that you were not from our neck of the woods.
Tag questions always swap negative values; like multiplying by minus one.
Although tags with two negatives are impossible:
*You never went there, didn't you?
*She isn't coming tonight, isn't she?
Tags with two positives do occur, as noted.
However, they are a different construction; they're not questions, but challenges:
She's coming tonight, is she?
The question is difficult, because the example itself is unwieldy at best. As Peter pointed out, few and a few have opposite meanings in this context, so it would be unusual to use either where there is risk of confusion. Since few here means 'not many', and simple reference to negatives gives us Not many people knew the way, did they?, I would say few also ...
While it's ultimately a matter of style and preference, I think the case for the period is very strong. The period makes the writing clearer without becoming a distraction, and that's what good punctuation should do.
Using italics to distinguish the two kinds of tag questions works, but adding more punctuation creates more distraction.
The only real ...
1A: [So,] I am impatient, am I?
would be used when you at last meet the chap who's been telling all your workmates that he thinks you're impatient.
1B: I am impatient, aren't I?
uses the usual tag question, here begrudgingly asking for confirmation (which one hopes will be given in a not-too-unpleasant way) of one's self-assessment.
2A: The class was ...
Strictly speaking all the first three could be considered "valid" (although #2 would be a somewhat contrived context, and would require the final "tag question" to be reversed into "..., will you?").
So I'd say this "online grammar test" is very poor quality, purely on the grounds that there's no single correct answer. All we can say for sure is #4 is a no-...
Have to is an idiom, a paraphrase of the modal auxiliary verb must; it's always pronounced /'hæftə/ (/'hæstə/ in 3SgPres -- always /f/ instead of /v/ and /s/ instead of /z/), and it can't be split up.
Modal paraphrase idioms like hafta, wanna, gotta, etc. are written with to in formal spelling, but that's just a marker for the infinitive that has to follow ...
As John Lawler says, below, “There is no asserted logical proposition in a question.” There is no ‘logical’ difference between Do you have a ticket? and Don’t you have a ticket? to be taken into consideration: both amount to the same thing, Do you … ?. The same is true of a third variant, You do have a ticket, don’t you?
The difference between them lies in ...
The question at the end is implicitly asking the listener to correct you: thus it invites the opposite response to what you have just said.
It isn't raining today, is it?
This invites a response of "It is raining", in case you are mistaken.
It's raining today, isn't it?
This invites a response of "It isn't raining", again in case you are mistaken.
I think the phrase you are looking for is rhetorical question. In this case, the speaker is using rhetoric in an aggressive way to chastise the listener for their perceived incompetence.
For example, I was person b in your first example only a couple nights ago. My friend complained that I didn't respond when he messaged me at 2am. Using a rhetorical ...
As the question stands, the OP asks if (forms of) mistake can be used as other than a noun (Should I write "... or I've made a mistake?").
In that sense, the "Capital of A is B, or I'm mistaken?" is correct in the use of mistaken as an adjective.
1. Wrong in one's opinion or judgment.
2. (esp. of a belief) ...
"Mind you" is not the question "do you mind?". It is just a shortened form of "keep X in mind". And of course, in the first example, "mind" is just a shortened form of "mind you".
a phrase introducing something that should be taken into consideration.
So your examples:
Both are correct, but there a difference in meaning
The first suggests that you are challenging a statement from someone else "He is too young to go to school"
The second, that you are seeking confirmation for the initial statement.
Whether the adjective implies negativity or not is irrelevant. A positive verb with a negative tag (or vice versa) suggests the speaker just about knows the answer but is seeking confirmation; a positive verb with a positive tag (or a negative verb with a negative tag) suggests confrontation, surprise, etc., on the part of the speaker.