1.
to accompany, to go together with
To come along with something as a natural or inseparable companion.
雷を伴う雨。
Rain accompanied by thunder.
成長に伴い、体も変わる。
As one grows, the body changes too.
人口増加に伴って、住宅不足が深刻になった。
Along with population growth, the housing shortage became serious.
2.
to entail, to involve, to bring with it
To necessarily include or require something as a consequence. Often used for risks, costs, or changes that come with an action.
危険を伴う仕事だ。
It's a job that involves danger.
手術には痛みが伴う。
Surgery entails pain.
大きな改革には、いつも犠牲が伴うものだ。
Major reforms always come with sacrifices.
伴う is used in both everyday and formal contexts to express that one thing comes with or brings along another.
TRANSITIVITY:
- Type: Both transitive and intransitive
- Transitive: 〜を伴う (to bring along ~, to involve ~)
- Intransitive: 〜に伴う / 〜に伴って (to accompany ~, along with ~)
ASPECT (ている):
- 伴っている: is accompanied by, involves (ongoing state)
COMMON PATTERNS:
- 〜に伴って / 〜に伴い: along with ~, as ~ occurs
- 〜を伴う: to involve ~, to be accompanied by ~
- 危険を伴う: to involve danger
- 痛みを伴う: to involve pain
USAGE: The pattern 〜に伴い is a more formal written alternative to 〜に伴って. Both mean "along with" or "as a result of."