Ecology is a field of study that investigates the interrelationships of organisms in the natural world.

This substance undergoes a chemical change when heat is applied.

In this experiment, the substance will undergo a chemical change.

He is majoring in agronomy at university.

My major is chemical engineering.

Fundamental interaction is one of the most important forces in physics.

He likes to take a walk in the park at dusk.

My younger brother belongs to the high school band.

He is an expert in dentistry.

This university has decided to close due to financial reasons.