marker; milepost; milestone

1. 祝賀你抵達了生命的又一個里程碑，愿你每天都象過生日一樣充滿喜悅。祝你生日無比快樂！
   Permit me to congratulate you on reaching another of these anniversary landmarks today. May each day be as happy as your birthday. Have a wonderful birthday!
2. 確立了法律判例的里程碑式的決定
   A landmark decision that set a legal precedent.
3. 里程碑，里程標(biāo)路邊所設(shè)立的石制標(biāo)志，以英里指示從給定的一點到該路標(biāo)的距離
   A stone marker set up on a roadside to indicate the distance in miles from a given point.
4. 每個生日都是我們人生之旅的一個里程碑，愿你的生日百事順意。
   Each birthday is a milestone we touch along life's way. May your birthday be happy in more ways than one.

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