Let's learn about "단추가 하나 떨어져 나갔어요"

셔츠 단추가 하나 떨어져 나갔어요 : A button from my shirt is missing; This shirt is missing a button; A button fell off; I’m missing a button.

ex)

A. 뭐 찾아? : What are you looking for?

B. 단추를 잃어버렸어. 이 근처 어딘가에 떨어진 것 같은데 : I’m missing a button, and I think I dropped it somewhere around here

[other expressions]

- 셔츠 단추가 하나 떨어져 나갔다. (to younger people or friends)

- 셔츠 단추가 하나 떨어져 나갔네. (to younger people or friends)

- 셔츠 단추가 하나 떨어져 나갔어. (to younger people or friends)

- 셔츠 단추가 하나 떨어져 나갔군! (to younger people or friends)

- 셔츠 단추가 하나 떨어져 나갔구나! (to younger people or friends)

- 셔츠 단추가 하나 떨어져 나갔네요. (honourific by '요')

- 셔츠 단추가 하나 떨어져 나갔군요! (honourific by '요')

- 셔츠 단추가 하나 떨어져 나갔어요. (honourific by '요')

- 셔츠 단추가 하나 떨어져 나갔습니다. (formal; more honourific by '스-‘)

[explanations]

* 셔츠 : shirts

* -의 : a particle makes 셔츠 possesive; this omitted

* 단추 : button

* -가 : a suffix makes 단추 subjective after a word ends in a vowel

* 하나 : one (button)

* 떨어지다 : (1) [=낙하하다·추락하다] fall; drop; get[have] a fall; come[go] down; be down; (비행기 등이) crash; (액체가) drip (2) [=(해·달이) 지다] set; sink; go down (3) [=분리되다] separate; part from[with]; fall apart (4) (붙었던 것이) come off; come apart; be off; become disjoined

* 떨어져 : 떨어지(the stem of 떨어지다) + -여(and then)

* 나가다 : (1) [=외출하기 위해 밖으로 가다] go out (2) [=못쓰게 되다] be broken; go wrong; get out of order; (전기 등이) go out; fail; be cut off <-- 나다(come out; move out) + 가다(go)

* 떨어져 나가다 : come off; fall off

* 나갔다 : past tense of 나가다 by '-았-'

* 나갔습니다 : 나갔(the stem of 나갔다) + -스(a suffix makes a verb more honourific) + -ㅂ니다(an honourific descriptive verb ending suffix)

* a verb + -다 / -네 / -어 / -지 : a non-honourific descriptive verb ending suffix

* a verb + -군! / -구나! : a non-honourific exclamatory verb ending suffix

* a verb + -네 / -어 / -군! + -요 : an honourific verb ending suffix

* a verb +  -습니다 / -ㅂ니다 : an honourific descriptive verb ending suffix by '스-' / '-ㅂ'