Grammar
-기도 하다
Meaning
Intermediate-gido hada
Attaches -기 (which nominalizes the verb/adjective) plus 도 하다 to mean 'also/sometimes do ~,' presenting the action or state as one possibility among others rather than the only or constant case. Softens a statement and often signals variety or occasional occurrence.
Form
Attach -기 to the verb or adjective stem to nominalize it, then add 도 하다: stem + 기도 하다. E.g., 웃다 → 웃기도 하다 (also/sometimes laughs), 예쁘다 → 예쁘기도 하다 (is also pretty at times). Conjugate 하다 for tense: 기도 했다 (also did, past), 기도 할 거예요 (will also do).
Examples
친구들과는 반말을 사용하기도 합니다.
I sometimes use casual speech with friends.
From: Age and Honorifics: Understanding Korean Speech Etiquette
가끔 늦잠을 자기도 해요.
I sometimes oversleep too.
그 영화는 슬프기도 하고 재미있기도 했다.
That movie was both sad and fun at times.
Common mistakes & nuance
Very often used in the paired pattern A기도 하고 B기도 하다 to say something has both qualities or varies ('sometimes A, sometimes B'). Note that '기도' also appears in the unrelated pattern -기 전에 ('before doing'; e.g. 하기 전에) — that 기 belongs to a different grammar point, not this one.
Similar grammar
- -고
Plain -고 simply lists actions or states without extra nuance ('does A and B'). -기도 하다, especially in the A기도 하고 B기도 하다 pattern, adds the nuance that these are just some of several possible cases, not an exhaustive or constant description.