因为经济原因，他大学时一边上课一边打工。

Yīnwèi jīngjì yuányīn, tā dàxué shí yìbiān shàngkè yìbiān dǎgōng.

Because of economic reasons, he worked while attending classes in college.

这个城市的经济发展得很快。

Zhè gè chéngshì de jīngjì fāzhǎn de hěn kuài.

The economy of this city is developing very fast.

他们在讨论国家的经济问题。

Tāmen zài tǎolùn guójiā de jīngjì wèntí.

They are discussing the country's economic issues.