cooperate, collaborate ((with))
- 彼と共同で執筆した
- I collaborated with him in writing it./I wrote it in collaboration with him.
- 共同で店を経営する
- run a store in partnership ((with))
- 車を共同で使用する
- share the use of a car
- 古家を3人の学生と共同で借りて住んでいる
- I'm sharing an old rented house with three students.
- 我々は共同で責任を負わねばならない
- We are jointly responsible for it./We must 「take joint [share the] responsibility for it.
- 共同で炊事をしている
- 〔農家などが〕They do their cooking in a communal kitchen.