More than two years have passed since the 50 Vietnamese families of Jefferson Village first left Saigon for Fairfax County, Va., but for many of them it will take more than time to remove their sense of loss and longing, of isolation and loneliness.

It will take, they say, the next generation.

Slowly they are making a world for themselves, one whose geographical boundaries are narrowly circumscribed to home and family and whose emotional frontiers are cloudy. They are watching, they say, history slip away, and they greet its retreat with varying degrees of fear, regret, and disbelief.

They have learned now to construct a creaky armor in which to joust with the world outside, where the food is bought, the work is done, the money earned. They have learned how, they say, to "act American on the outside" while remaining "Vietnamese on the inside."

Outside is the world around the Jefferson Village apartment complex, which lies next to U.S. Rte. 50 as it slices past Loehmann's Plaza Shopping Center in Fairfax County.

Jefferson Village is an inconspicuous nook of the American cultural landscape, a scene recreated thousands of times along the length and breadth of this country. To the Vietnamese who live here, it represents a foreign and frightening world, against which the red brick walls of their apartments serve as both buffer and barrier.

Nguyen Van Tu sits in a battered easy chair in his living room, surrounded by cast-off furniture, the floor a patchwork sea of odds and ends of other people's carpet. His long, elegant hands finger the air, as if to catch stray thoughts there.

The process of adapting to this strange country has been an adventure for his six children, he says. For him and his wife, it has been "exhaustive."

He and his family moved to Jefferson Village last December, after living for 16 months in Springfield. "We tried to adjust," he said, but Springfield seemed an alien place, and there was an uneasiness to life without the comfort of the familiar.

So they had moved to Jefferson Village where friends had told them more Vietnamese families lived. "Here," he said, "we have people we can communicate with."

In Vietnam, he had grown up among the elite. As a young man, he had studied economics and sociology in Paris. As a senior artillery officer, he had traveled twice to the United States - in 1959, to attend artillery school in Oklahoma, and again in 1970 to study psychological warfare at Fort Bragg, N.C.

Now he works in the boiler room at George Mason University, supporting his wife and six children on a salary of $600 a month. Four nights a week, he attends classes at W.T. Woodson High School to upgrade his newly acquired skills as a steam engineer.

His conversation returns again and again to the hard scratch for a living that life has become. It tempers the way he sees the world now, past, present and future. "I worry constantly," he says, "about money."

He came here, he said without any skills sellable in the marketplace. "In Vietnam," he said, "my education was heavily influenced by Confucian principles. A man was born to be either a laborer, a merchant, a farmer or a scholar. And if he was raised to be a scholar, he did not concern himself with the practical."

Here, he continued, "economic and social position are based on the skills a man has," and it has been a hard struggle to replace Confucius with Horatio Alger.

Now, he says, his most overriding concern is that his children "get an education that will get them a job."

His 14-year-old daughter bounds through the small living room, dressed in faded blue jeans and a T-shirt, a plastic comb in a hip pocket, her eyes betraying nothing of the private world of adolescence.

He watches her cross the room. He is, he says, "a little worried" about his children. The tightly disciplined, hierarchiacal world of the Vietnamese family is changing.

The relative ease of his children's adaptation gains them an independence they would not have had in Vietnam."Discipline," he says, "is looser here. In Vietnam, they asked my permission to go see their friends, to do almost anything. Here, they just go."

They will grow up more assimilated then he will ever be, less tied to the family. "Sometimes," he says, "I feel that is not what I want." But, he says with a slight nod to circumstance, "if they become more independent, that reduces my care."

He pulls a thread from his Confucian training to explain his meaning. "Sometimes," he says, "the contradictions meet. Fire is opposed to water, but from fire, you get warm water."

It is his wife, he says, who is finding the slow halting steps toward adjustment the hardest. "She says the people are not happy here, because they rush around all the time," he says.

She knows little English, says Nguyen Van Tu, so her trips outside of Jefferson Village are limited to a nearby supermarket, where "she can read the prices correctly" and to an occasional garage sale, where she searches for souvenirs from Vietnam that Americans, who were in her country only briefly and often reluctantly, are now tossing aside. On the street outside her home, she smiles and says hello to "every American lady who passes by," her husband says. It is just about all the English she knows.

It is the wives, say the husbands, for whom this new world is the most frightening of places and their isolation from it introduces its own friction into the family. "It is hard," said one man, "when the husband speaks English, and the wife does not. We watch the TV, and my wife gets angry because I understand and she doesn't. And I become angry at her for not learning the language, for not adjusting. She has to see everything through another person's eyes."

To help resolve the loneliness, said this man, who refused to be identified, "she is thinking of having another child.I'm against it and she can't understand. But someday, it might be possible to return to Vietnam, and a child born here might make it more difficult."

Difficult as well, to varying degrees, is the embarassment that lowered financial circumstances in this country often brings to a refugee in Jefferson Village.

The clash of images is most apparent when talking to Nguyen Van Tu, the elegant ex-officer home from his shift in the boiler room. Tu smiles when he is asked if there is a shame attached to the plummet of his social status. "No," he said, "here, it is different. Here, the top is very small and the middle is very big."

For others, however, pride was left in the dust of Saigon streets as they left in the chaos of those last few days of April, 1975.

One man who lives now in Jefferson Village would talk to a reporter only on the telephone. He is ashamed, he said, of the "shabbiness" of his apartment, and the shame acts as a rein on any social contact with Americans, cloaking his communion with others in inhibition and restraints.

He does not go out to movies or to restaurants or any of the outside pleasures a summer evening might bring. "I feel comfortable only in my home," he said. "I don't have the right clothes, the right kind of home. At parties," he said, "it is so embarassing. We don't drink like Americans do, we are not so open with our thoughts and feelings."

Even introductions to strangers can be a source of fear. The Vietnamese, he said, traditionally do not call each other by their given names and the structure of American names are a mystery to him. "I know I will forget them in the middle," he said, "and so I am always very nervous."

Unlike Nguyen Van Tu, this man finds no relief in philosophy or in the daily scrape to earn a living. Taken out of the country and the context in which he had lived his life and fashioned his dreams, he spends his time "forced now to reflect upon myself, who I am and what I'm doing. Nothing can be assumed any longer and you cannot know what that means.

"Suddenly, everything becomes insignificant and life, in the end, is to be endured. It is hard to know that for the rest of my life, I will never feel at ease. Now I am a man who has to live in his memories."

The other Vietnamese families who live in Jefferson Village provide him with little comfort. "There are people who live here," he sad, referring to former high ranking military officers, "who didn't contribute anything to the war. They exploited it. They tried to take money out of the country. Personally, I hate them, I despise them. But here we are, living in the same boat. At least a lot of them are worse off than me."

He paused, for a moment, taken aback by his own bitterness. "You see," he said, "there is no togetherness in the Vietnamese community at all. It's a sad fact, but we behave as if we were still at war. War changes people. They don't trust one another, they don't help one another. We are strangers here."

There are those who live in Jefferson Village, however, who walk a narrow line, trying to adopt those values that seem to insure success in the strange culture in which they find themselves, while carefully insulating themselves from whatever might sever their lifelines to the past.

From the beginning, said Nguyen Thu Ho, in the days before Saigon fell, he tried to prepare his family of eight for the life they would find in America. The vision he presents is grim.

"I told them before we left that the U.S. is not a rosy garden at all," Ho said. "That here everybody worked, not like in Vietnam. My wife did not want to get a job. In Vietnam, she had a life of her own, she stayed home and took care of the children. Over here, I told her that she has to go to work. Now she knows that to live in America she has to compete. You have to work and in any workshop you have to compete or you will be eliminated."

After spending a year in California, working 12 hours a day as a machine line operator in a plastics factory, Ho moved his family to Fairfax because he had heard that "Americans value engineering and computers."

Now he works for the Xerox Corporation, earning $850 a month as an assembler and tester. "They call us technicians," he said, "but we are really just skilled laborers." His wife works as a cook for a catering service, Oriental Food Enterprises.

They are like homesteaders here, forcing a stake into the suburban frontier. On the weekends, Ho fishes the Potomac, to supplement the family income. The family maintains a vegetable garden on the small plot of grass outside their apartment, which, Ho said, saves him $10 a week. In Saigon, he said, the days were different.

There he worked as an administrative officer for the U.S. Agency for International Development. "After the rush hour," he said, "I didn't go home straightly." Instead, he would walk along the crowded streets, stopping by a beer stand, dropping in to have a drink with friends, savoring day's end and evening's beginning. At 8 p.m., he would stroll home, where wife, children and dinner would be waiting.

But here, he said, the entire family is up by 5 a.m. At 3:30 p.m. he picks up his wife at work, and then hurries home to supervise the children's homework, tend the garden and prepare for the following day. "Here," he said, "you have to rush. You live by the clock, you compete with time."

There is no rush to adopt an intrinsically American way of life. It is Vietnamese holidays that are celebrated, Vietnamese dinners that are prepared, and Vietnamese music that plays on a tape cassette as Ho says that they are taking time to assimilate in order to "prevent shock."

For his family, he said, "I do not want the change to be considerable. It is for my grandchildren that change will be great."