That plan is too impractical, it's difficult to implement.

His plan was so unrealistic that no one could believe it.

He works at a non-governmental organization.

His glasses are for correcting astigmatism.

This design has a unique charm because it is asymmetrical.

That theory is unscientific and has no evidence at all.

Amorphous substances have characteristics different from crystals.

I'm troubled by his unproductive attitude.

He feels that he is a person not fulfilled in real life.

He is thought to be a very unsociable person.