2.the church steeple provided a convenient landmark.
3.The tower was once a landmark for ships.
4.A prominent identifying feature of a landscape.
5.The pavilion on the hilltop was a well-known landmark.
6.You also need to study a map of your target area and note any landmarks.
7.Our key insight was the realization that different xenon isotopes in our Oklo sample were created at different times—following a schedule that depended on the half-lives of their iodine parents and tellurium grandparents.
我们的关键性认知是理解到，欧克
陆标本中各种氙同位素是在不同时间生成的，时程表取决于它们的母元素碘和再上一代元素碲的半衰期。
