During this time period, the region experienced many changes of national borders.

International trade is the exchange of goods and services across national borders.

The reservoir, however, did not fill past the national border until 1954.

They were considered one village until the national border was drawn in 1809.

The issue of protecting national borders is one that every nation needs to face.

In my opinion, this is not related to national borders.

It has in the past been possible to watch television across national borders.

This is difficult to understand, for when do roads ever stop at national borders?

However, we will also need public participation across national borders.

Care areas need not stop at national borders by definition.