CONCEPTS: crash, plane, tower

GEN: a plane hijacked by terrorists crashed into north tower .

CONCEPTS: bridge, cyclist, pedestrian

GEN: traffic of cyclist and pedestrian on a bridge in town

CONCEPTS: frost, lawn, year

GEN: last frost on the lawn for the year

CONCEPTS: bathtub, edge, towel

GEN:
A white towel is at the edge of a white bathtub.