Organic solvents play an important role in chemical reactions.

The software is currently being configured.

This system needs reconfiguration.

He reconstructed the broken house.

All members of our team are experts.

Constructivism is an educational theory that knowledge is actively constructed by each learner.

Calcium carbide is a major raw material for acetylene gas.

He has a very passive personality.

He was involved in the development of the hydrogen bomb.

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