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relation; relationship; connection
participation; involvement; concern
influence; effect
related to; connected to
sexual relations; sexual relationship
仕事の関係で来週出張に行きます。
I will go on a business trip next week due to work-related matters.
それは私には関係のない話だ。
That's a matter that doesn't concern me.
両者の関係を詳しく調べている。
Investigate relationship.