This bottle is reusable.

Who is the user of this software?

He is the most competent employee of our company.

Are you really not going to use this unused laptop?

His body showed a rejection reaction to the transplanted organ.

This chemical reaction is very dangerous.

She overreacted to his words.

Nuclear reactions are used for mass production of energy.

I was surprised by his overreaction.

The ecosystem of this lake heavily depends on a specific food chain.