Do you understand the necessity of this project?

That information is unnecessary.

That information is completely unnecessary.

He thinks that war is a necessary evil.

Transition metals play an important role in chemical reactions.

When he opened the door, a metallic sound echoed.

Alkali metals are very reactive chemically.

Metallic bonds are formed by ions floating in a sea of electrons.

He changed his diet to improve his life.

This project needs digitalization.