milestone
n
1 stone put at the side of a road showing distances in miles 里程碑. 2 (fig 比喻) very important stage or event 重大阶段或事件; 转折点
This victory was a milestone in our country's history. 这一胜利是我国历史的转捩点.
No, we didn't fix anything. We thought we might go out, but we said we'd check with each other first. And now I'm telling you I can't manage this Friday. Another time, possibly, but not Friday.