His robot caused the phenomenon of the uncanny valley.

The impact of the unequal treaty is still deeply rooted in our society.

This mask is made of non-woven cloth.

He is a bungler, so he is not good at detailed work.

I'm troubled by his lack of seriousness.

He has an unserious attitude towards his work.

He always shows a frustrated attitude.

He always feels frustrated.

The success of this project is influenced by a lot of uncertainty.

Sometimes, irrational things happen in this world.