Mileposts
n. 里程碑；里程标志
🗣️ 情景例句
What did you do?
那你怎么办呢？
Don't take it seriously.
不要当真。
So it is a comparatively simple step from locating the sea bottom to locating a shoal of fish.
从测定海深到测定鱼群，这一进展比较容易。