Antibiotics don't work for colds, so rest is the best.

A day has 24 hours.

He ate one apple.

It is important for each person to fulfill their role.

The air in this area is greatly affected by pollutants emitted from factories.

The existence of dark matter has not yet been fully proven.

It is said that antimatter has properties opposite to those of matter.

We exist as a part of the material world.

This food may contain carcinogens.

He acted according to my instructions one by one.