"Do the students stand up?"

Translation: 학생들이 일어서니?

[Demonym281]

I thought 해요체 didn't have to change forms when turning into a question? I think ~서니 must be 해체 but I haven't seen it mentioned before in the course notes

[rkirsling]

일어서다 is the verb, 니 is the suffix.

[61ackJack]

~서니 is actually 해라체, and actually forms in 해요체 and 해체 doesn't change at all in questions.

[moira142592]

can @duolingo explain why the 느냐 form is not accepted here?
In the same section of exercices sometimes both ~느냐 and ~니 are accepted, sometimes only one and I don't seem to see why. According to your own tips: https://www.duolingo.com/skill/ko/Written/tips-and-notes
It is said that

When asking a question in 해라체, simply add ~느냐 or ~니 to the verb stem.

So can @duolingo please either explain why only one or the other form should be accepted (or why both)? and at least be more specific in the tips if a difference should be made.

[mhin1]

Relevant Comment

[kinkybottom]

When is it 일어나다 and when 일어서다?

[SbastienLe60464]

I never know if DL wants us to be explicit with the plural. It's quite frustrating.