There are many things placed in my room.

His travel story was very interesting.

Physics is a difficult subject.

This is my precious thing.

He created a new story.

That's a new thing, isn't it?

Hydrogen sulphide is extremely toxic, and particularly at high concentrations, it is lethal to humans.

Hydrocarbons are fundamental components of organic chemistry.

He was involved in the development of the hydrogen bomb.

Decolonization is an important process for many countries to achieve independence.