He is using a hand-held net to catch fish in the river.

He caught fish in the river using a fish-trap.

This photo can express details because it has a high density of halftone dots.

The railway network in Japan is very developed.

The Adige is the second longest river in Italy.

The Congo River is the largest river in Africa.

The Danube is one of the longest rivers in Europe.

The Aar river is one of the beautiful rivers in Switzerland.

The Don is one of the important rivers in Russia.

The Euphrates is one of the major rivers in the Middle East.