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slope; incline; hill
milestone; (age) mark
この坂を上ると駅に着きます。
If you go up this hill, you'll reach the station.
彼は五十の坂を越えたばかりだ。
He has just passed the fifty mark.
坂道を自転車で下るのは危ない。
It's dangerous to go down a slope on a bicycle.