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to have been decided (so) that; to have been arranged (so) that
to be the result (of); to be the outcome
to be the reason (for)
来月から転勤することになった。
It has been decided that I will transfer next month.
会議は中止ということになります。
It will be decided that the meeting is cancelled.
来年結婚することになる。
It will be decided that I will get married next year.