NANNING, Aug. 19 (Xinhua) -- Every morning, more than 7,000 Vietnamese walk across the border and start work in a Chinese town.

Nguyen Thi Dung, an interpreter, is one of them. She lives in the Vietnamese city of Mong Cai but works in Dongxing City in China's Guangxi Zhuang Autonomous Region.

The 27-year-old woman has a number of clients in Dongxing. With the help of people like her, Vietnam sells seafood to China, while China exports clothes and domestic appliances to Southeast Asia.

Dung earns at least 200 yuan (about 33 U.S. dollars) every day, nearly five times the amount of the average Vietnamese do.

"It's been my dream for a long time to speak Chinese well and work in China," she said.

The free trade area built by China and the Association of Southeast Asian Nations (ASEAN) provides opportunities for more people to make decent salaries like Dung.

The preferential trade policies and zero tariffs for thousands of commodities have resulted in an increasing number of Chinese and ASEAN citizens working across borders.

Vietnamese businesswoman Lu Thi Mot started to seek opportunities in Dongxing a decade ago.

After years of hard work, Mot now runs a Vietnamese specialty store at a trade center in Dongxing.

Every morning, Mot walks to her store in China, and in the afternoon, she returns to home in Vietnam. Her business is booming.

Chinese living in the border area can buy up to 8,000 yuan of Vietnamese goods every day without paying tariffs. This has resulted in mushrooming border transactions.