He utilized his project management skills to start a new business.

He was observing a three-dimensional image using a stereoscope.

He learned about substantialism in his philosophy class.

He is working hard to substantiate that idea.

His dream finally became a reality.

His explanation was impossible to understand.

He thinks that war is a necessary evil.

Do you understand the necessity of this project?

That information is unnecessary.

That information is completely unnecessary.