In recent years, tension has heightened around the anniversary date each year.
The tension was heightening very fast; it must go no higher.
"Why heighten tensions if you got no rationale for it?"
Tension between central and local government heightened in the final years of the Soviet Union's existence.
Tension heightens between the two nations as a result.
As a result the drama is compressed, the tension heightened with the ticking clock.
Maybe tension had heightened his normal perceptions; maybe he was imagining things.
Tension between the couple heightens by a mysterious room in the shed, which Fernando keeps closed from his family.
The tension heightened as we crossed the border.
The book's tensions heighten as it moves inevitably toward revelation and finger-pointing.