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

His travel story was very interesting.

Physics is a difficult subject.

There are many things placed in my room.

There are a lot of old furniture in the storage room.

His single word triggered a chain reaction, and everything changed.

Nuclear reactions are used for mass production of energy.

I was surprised by his overreaction.

His body showed a rejection reaction to the transplanted organ.

Calcium oxide is one of the main components of cement.