This area has a lot of unexploded ordnance left over from the war, so caution is necessary.

The library is my favorite place to study.

In this area, many unexploded ordnances are found as a remnant of the war.

That landmine was a dud.

We installed a device to purify the water of the river.

We need to understand the importance of water purification.

He used a stone as a projectile.

I see dogs in the park every day.

His behavior is really disgraceful.

This area is still undeveloped and rich in nature.