经济学的原理可以解释消费者行为。

The principles of ___economics can explain consumer behavior.

经济学帮助我们理解市场如何分配有限的资源。

___Economics helps us understand how markets allocate scarce resources.

政府正在研究公共交通系统的运营经济学。

The government is studying the ___economics of operating the public transport system.

投资太阳能的经济效益在长期来看非常可观。

The ___economics of investing in solar energy look promising in the long run.