Paleoecology studies the interaction between organisms and the environment in the past.

Classical physics is an important part of human civilization.

Classical physics studies the fundamental laws of matter and energy.

Cervical cancer is a dangerous disease.

Classical economics has laid the foundation for many modern economic theories.

Neoliberalism is causing a lot of controversy in today's society.

Neoclassical economics is becoming a hot topic in modern economic research.

The entrance gate to that park is very beautiful.

He often has premarital sex with his girlfriend.

I went through the turnstile at the airport.