11.   In Laos, the North Vietnamese would be seen as foreign invaders.

12.   In ordinary allergies, the immune system reacts to innocent substances like pollen, dust mites or cat dander grains as if they were foreign invaders.

13.   It acts like a scavenger and culls foreign invaders such as pesticides.

14.   It is shifting its targets from foreign invaders to internal security threats and its energies from the battlefield to the marketplace.

15.   Most of the worst garden pests are foreign invaders.

16.   One of the plague proteins is a toxin that prevents the macrophage from engulfing foreign invaders, including the bacterium sitting on its surface.

17.   Sexual harassment is a particularly explosive issue in Korea, which has seen its women sexually mistreated by a series of foreign invaders.

18.   Specifically, Running Stag may have run his best race in his first US race, as so many foreign invaders do.

19.   The body then recognizes this antibody as a foreign invader and the immune system begins an attack that destroys only those cells to which the antibody is attached.

20.   The fractious Afghans united against the foreign invaders.