교체하다 (gyo-che-ha-da, gyochehada) · 교체되다 (gyo-che-doe-da, gyochedoeda)
교체하다 (gyochehada) denotes an active action of replacing by someone, while 교체되다 (gyochedoeda) expresses a passive state of being replaced by someone.
One lane per word — no nested boxes, just the gist.
An active action where someone directly replaces or substitutes something
When to use
Replacing machine parts, Replacing people, Expressing direct action
The nuance
Used when the subject actively performs the replacement. It is an active voice verb.
A passive state where something is replaced or substituted by someone
When to use
Automatic replacement of machine parts, Describing people being replaced, Emphasizing passive state
The nuance
Used when the subject is passively replaced in the situation. It is a passive voice verb.
기계 부품을 교체해야 합니다.
gi-gye bu-pum-eul gyo-che-hae-ya hap-ni-da., gi gye bu pum eul gyo che hae ya hap ni da.
Active subject clearly replaces parts, so 교체하다 is correct.
기계 부품이 교체되어야 합니다.
gi-gye bu-pum-i gyo-che-doe-eo-ya hap-ni-da., gi gye bu pum i gyo che doe eo ya hap ni da.
Parts are passively replaced, so 교체되다 is correct.
사장이 교체되었다.
sa-jang-i gyo-che-doe-eoss-da., sa jang i gyo che doe eoss da.
The CEO is passively replaced, so 교체되다 fits.
사장을 교체했다.
sa-jang-eul gyo-che-haess-da., sa jang eul gyo che haess da.
Someone actively replaced the CEO, so 교체하다 is correct.
기계 부품을 교체되었다.
gi-gye bu-pum-eul gyo-che-doe-eoss-da., gi gye bu pum eul gyo che doe eoss da.
Subject is not active agent; must use 교체되다 instead.
사장을 교체되었다.
sa-jang-eul gyo-che-doe-eoss-da., sa jang eul gyo che doe eoss da.
교체되다 requires the subject to be replaced; '사장을' is object form, so wrong.
직원을 교체되었다.
jik-won-eul gyo-che-doe-eoss-da., jik won eul gyo che doe eoss da.
Active replacement requires 교체하다; 교체되다 needs subject form, so incorrect.
직원이 교체되었다.
jik-won-i gyo-che-doe-eoss-da., jik won i gyo che doe eoss da.
Employee is subject expressing passive replacement, so 교체되다 is correct.
Which sentence shows active replacement?
Which sentence expresses passive replacement?
Why is "기계 부품을 교체되었다" incorrect?
