розширити 英語で:

Television helps us widen our knowledge.

They're widening the road.

Why are roads sometimes widened? Roads are sometimes widened because there's much too much traffic.

The road is being widened to two lanes.

to widen one's knowledge - poszerzyć swą wiedzę

They should widen this street because it is too narrow

His eyes widened as he saw the blood in the air