Mary was also a temptation for potential invaders such as Philip II.

Above each door was a small room filled with boulders and rubble poised to fall on any potential invader.

Invasion was more likely in ecosystems that were similar to the one in which the potential invader evolved.

It is widely believed that the choice was made for military reasons, to prevent potential invaders from using the Russian rail system.

She hoped they weren't good enough to spot the leeches she'd left for potential invaders.

It was intended to prevent the supply rail from potential invaders.

Moreover, many potential invaders are microscopic and almost impossible to detect.

In order to prosper and maintain its wealth, the city of Ypres had to be fortified, to keep out potential invaders.

This inherent instability in the countryside drew the unwanted attention of potential invaders.

Its occupants would have had a view of the countryside as well as any potential invaders.