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to have been decided (so) that; to have been arranged (so) that
来月から新体制で運営することとなった。
It has been decided to operate under a new system from next month.
転勤することとなって、引っ越しの準備を始めた。
Having been assigned a transfer, I started preparing to move.
会議は来週開催されることとなっている。
The meeting has been arranged to be held next week.