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increasingly; more and more; decreasingly (when declining); less and less
気温が増す増す上がって暑さが厳しくなった。
The temperature is rising more and more, making the heat severe.
雨で川の水が増す増す増えている。
The river water is increasing more and more due to the rain.
増す増す忙しくなる。
It's getting busier and busier.