The river formed the frontier between the land of the Saxons and that of the Danes.

这条河曾是撒克逊人与古斯堪的纳维亚人土地的分界线。

《牛津词典》

XML is certainly near the transition from a rough frontier-land to a mature technology run by a mature community.

当然XML已处于从一项简陋的前沿技术转变为由成熟社区管理的成熟语言的时刻。

youdao

Worldwide food shortages and rock-bottom land prices in Paraguay have made the Chaco the last agricultural frontier.

全球范围的粮食短缺以及巴拉圭岩石底土地价格的飞涨，终于让查科变成了人们争相获取的最后一片农业用地。

youdao

Thousands more are reported trapped in a no-man's land between the violence at their backs and a frontier ahead of them.

VOA: standard.2010.06.15

But when that's not true, then there is a typical sort of modern frontier, a land bridge which there a line is-a theoretical line is drawn through it, and on one side is one city, and the other side is another city.

但还不止这些天然边界,另外还有种边界形式,和现代国境线很类似,是由一座陆桥,分割出一条界线…假象的界线,界线的一边是一个城邦,另一边是另一个城邦

耶鲁公开课 - 古希腊历史简介课程节选

It will also mean an effective re-division of the land, making towns frontier towns again.

CNN: A wary welcome of peace in Israel - Sept. 27, 1995

The truth is that this has always been frontier land, and Armenians and Muslims have co-existed locally for centuries.

ECONOMIST: Letter from Karabakh