Let’s learn about "-잖아요”

* a verb + -잖니 / 잖나 / 잖어 / 잖아 : It is used as a suffix to say resentful things accompanied by irritation about not doing something in advance to the listener or to say things that must be hoped for by the listener's response; these are a non-honourific descriptive verb ending suffix

==> this is used when the speaker confirms a fact that the listener already knows or has forgotten

==> this means "as you know/ recall...~remind something that listener forgot/unaware or scold for not following advice"

* a verb + -잖나요 / -잖어요 / -잖아요 / -잖습니까 : : It is used as a suffix to say resentful things accompanied by irritation about not doing something in advance to the listener or to say things that must be hoped for by the listener's response; these are an honourific descriptive verb ending suffix by ‘-요’ / ‘-습’

==> this is used when the speaker confirms a fact that the listener already knows or has forgotten

==> this means "as you know/ recall...~remind something that listener forgot/unaware or scold for not following advice"

* See the followings about "-잖아요”

- https://m.youtube.com/watch?v=VHsLKLHBAVk

- https://m.youtube.com/watch?v=B-TI7UEGgSU

- https://m.youtube.com/watch?v=1IEHlRSnkyg

- https://m.youtube.com/watch?v=O3LKE8mB9DQ

- https://www.howtostudykorean.com/upper-intermediate-korean-grammar/unit-4-lessons-84-91/lesson-90/?amp

- https://sayhikorean.blogspot.com/2018/09/korean-grammar-expressing-reasons_15.html?m=1

- https://www.koreantopik.com/2017/02/l2g12-avn-grammar-as-you-know.html?m=1

- https://www.koreanwikiproject.com/wiki/%EC%9E%96%EC%95%84%EC%9A%94

- http://ohmykorean.com/?p=146