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together; jointly
at the same time; with; as ...; including; along with
both
困難を共に乗り越えましょう。
Let's overcome difficulties together.
経済の発展と共に生活も変わった。
Life changed along with economic development.
友人と共に素晴らしい旅行を楽しんだ。
I enjoyed traveling together with my friends.