Due to the earthquake, the city declared a state of emergency.

He broke the glass carelessly.

His carelessness caused the accident.

Do you understand the necessity of this project?

That information is unnecessary.

That information is completely unnecessary.

He was paying attention to the teacher's talk during the class.

He thinks that war is a necessary evil.

This issue requires attention.

The air in this area is greatly affected by pollutants emitted from factories.