Tanya Davis fled Jizhou No. 1 Middle School one winter morning in March before the sun rose over the surrounding cotton fields covered with stubble from last fall's crop.
In the nine months Davis and her boyfriend had taught English at the school in rural north China, they had endured extra work hours, unpaid salaries and frigid temperatures without heating and, on many days, electricity.
Hearts pounding and worried their employer would find a pretext to stop them leaving, the couple lugged their backpacks, suitcase, books and guitar past a sleeping guard and into a taxi.
As they drove away, "the sense of relief was immense," said Davis, a petite, soft-spoken 23-year-old from Wales. "I felt like we had crossed our last hurdle and everything was going to be OK."
It's a new twist on globalization: For decades, Chinese made their way to the West, often illegally, to end up doing dangerous, low-paying jobs in sweatshop conditions. Now some foreigners drawn by China's growth and hunger for English lessons are landing in the schoolhouse version of the sweatshop.
In one case, an American ended up dead. Darren Russell, 35, from Calabasas, California, died under mysterious circumstances days after a dispute caused him to quit his teaching job in the southern city of Guangzhou.
"I'm so scared. I need to get out of here," Russell said in a message left on his father's cellphone hours before his death in what Chinese authorities said was a traffic accident.
As China opens up to the world, public and private English-language schools are proliferating. While most treat their foreign teachers decently, and monthly wages can run to US$1,000 plus board, lodging and even airfare home, complaints about bad experiences in fly-by-night operations are on the rise. The British embassy in Beijing warns on its Web site about breaches of contracts, unpaid wages and broken promises. The US embassy says complaints have increased eightfold since 2004 to two a week on average.
Though foreign teachers in South Korea, Japan and other countries have run into similar problems, the number of allegations in China is much higher because "the rule of law is still not firmly in place," said a US embassy official who spoke on condition of anonymity.
"A number of substandard English language teaching mills have sprung up, seeking to maximize profits while minimizing services," the US House of Representatives International Relations Committee said in a recent report on Russell's case. These institutes have become virtual "`sweatshops' where young, often naive Americans are held as virtual indentured servants."
Davis said officials at her school in Hebei Province piled on classes without compensation, dragged their feet on repairing leaks in her apartment and would deduct sums from her US$625 monthly salary for random taxes and phone calls that were never made. These ranged from US$30 to US$85, she said.
She recalled nights without electricity when there was nothing to do but sit in candlelight.
The more "we let them get away with, the more they tried to get away with," said Davis, who now teaches piano in Beijing.
Numbers are hard to track. The Education Ministry said there was no record of how many language schools exist, because local governments administer them. Education bureau officials in Bei-jing, Guangzhou and Shanghai -- China's major metropolises -- did not respond to telephone and fax requests for information.