Three in four immigrants interested in the free English classes at the Forest Hills Community House’s Jackson Heights branch are turned away.

So fierce is the competition for spots that, until recently, police officers were needed to regulate the block-long line that would start forming in front of the neighboring sari shops, the Argentinean barbecue restaurant, and the Iranian jewelry stores hours before the time of the lottery for class placement.

A new appointment system eliminated the line – and the need for police – but the demand remains the same.

“They can’t keep a waiting list because it would be a thousand people,” the executive director of the Literacy Assistance Center, Elyse Rudolph, said. The center serves as a clearinghouse for information on English classes and vocational training in New York City, and also runs teacher training programs.

When an immigrant wins a spot to take a class, Ms. Rudolph said, “It’s literally like winning $10,000, because that’s what it’s worth to them.”

According to statistics from the 2000 census, nearly one-quarter of adult New Yorkers, or about 1.5 million people, have a problem speaking English. The Department of City Planning reported a 30% increase during the 1990s, linked to an influx of new immigrants, and the city’s demographer, Joseph Salvo, said recently he sees no signs the pattern will change.

The city has a severe shortage of English classes for adults. The Literacy Assistance Center counts just 56,000 adult literacy spots in the five boroughs.

At Jackson Heights, a Queens neighborhood where about two-thirds of the residents are foreign-born, it’s a shift that the director of the branch, K.C. Williams, has watched over 15 years as she has gone from teaching one English class at the site to administering a staff of eight teachers. Today, she said, “The demand here is enormous.”

It’s more than just a supply-and-demand equation, however, that distinguishes the Jackson Heights site. There’s Ms. Williams’s tireless devotion to the program.” They’re very responsive to the community,” Ms. Rudolph said. “They’re very connected, and they’re able to provide the exact services needed.”

As a sort of one-stop service provider for immigrants, the Jackson Heights program, at 37th Avenue and 74th Street, offers legal advice, employment assistance, computer instruction, and community activities, in addition to excellent classes for people learning English or learning to read and write.

Like many city’s programs, a fluctuating mix of federal, state, and city funds supports the Jackson Heights program.

Recently, an alarm went through the immigrant services community when President Bush’s preliminary budget for the 2006 fiscal year was announced. Mr. Bush cut funds for adult education by nearly two-thirds. That would “just be devastating” to her program, Ms. Williams said.

Over the course of each weekday, 600 students speaking more than 30 languages flow through the center’s modest classrooms. Generally, results of the program, which provides intensive, five-day-a-week classes, far surpass state standards. Recent graduates who arrived with no English have gone on to a research assistantship at Mount Sinai Hospital, service in the war in Iraq, and a position directing a day-care center.

Whether the students are from Indonesia, Colombia, or Israel, their reasons for studying are generally the same: They want to talk to their children’s teachers, to understand doctors, to be able to ask directions when lost in Manhattan, and, foremost, to get a job.

And whether they arrive illiterate or highly educated, all the students share the humbling struggle of learning English as an adult.

“It’s not washing the flowers,” a teacher gently corrected a student in a beginner’s class on a recent afternoon, “it’s washing the floors.” When the student, a recent South American immigrant, understood the mistake, she let out an embarrassed giggle.

In the front of the class, a middle-aged librarian from China exchanged notes with a young housewife from Bangladesh. Farther down the row sat an Ecuadorian immigrant with dark circles under his eyes, Nilo Madera. As he wrestled to form basic sentences, beads of sweat lined his brow. Finding time for the class in between graveyard shifts as a parking attendant in Manhattan appeared to be taking its toll.

That type of dedication to learning English is not the exception but the rule, Ms. Williams said. “People don’t come here to learn English because it’s a pretty language,” she said. “They come here because English is the tool to improve their lives and their family’s lives in this country.”