The population is increasing rapidly.

I think yesterday's test was more difficult than ever.

The strength of this bridge is very high.

This house is made entirely of wood.

Carbonization is a type of chemical reaction where organic matter changes under high temperatures and in a state of oxygen deficiency, turning into a substance with carbon as its main component.

When this wood is carbonized, its strength increases.

Hydrocarbons are fundamental components of organic chemistry.

Calcium carbide is a major raw material for acetylene gas.

Alkynes play an important role in organic chemistry.

Alkenes play an important role in organic chemistry.