Salmon return to their spawning grounds by going upstream.

Salmons make a great effort to go upstream the river.

Modern society classes are important for a deep understanding of history and contemporary society.

The final boss of this game is very powerful.

He received training to drive an armoured car.

His plan is already on the chopping board.

In this chemical reaction, sodium plays an important role.

This sculpture was made using sandblasting technology.

He sandblasted the wall.