but the line they dare not cross is to splice human genetic material into an experiment.

VOA: standard.2010.06.09

Working in secret, they cross that line. The result is horrifying yet mesmerizing.

VOA: standard.2010.06.09

and Mexican officials. Every day, thousands of people on foot and in vehicles go back and forth across the border here, and millions of dollars worth of products cross the line in trucks and railroad cars.

VOA: standard.2009.04.30

The Greek Cypriots canceled the latest session Thursday after Turkish Cypriot authorities held up a bus convoy of Greek pilgrims for lengthy security checks as they sought to cross the dividing line between the communities.

VOA: standard.2009.09.05