NEW YORK (AP) _ Teacher Milton Evertz leaned down and spoke inches from his pupil Maria's ear: ''Listen to me. Say it just as I'm saying it: 'West. West. West. West.'''

''Wet. Wet. Wet,'' she replied, finding the letter ''s'' a challenge for her Hispanic tongue.

''You mean, like, ''mojado?'' asked Evertz, laughing heartily and drawing a smile from Maria as he spoke the Spanish word for ''wet.''

So it goes two evenings each week for the 14 formerly illegal aliens in Evertz's ''amnesty class'' at Hostos Community College in the South Bronx, one of several campuses of the City University of New York offering such courses.

For the more than half a million immigrants nationwide who have so far completed these classes - 100,000 in New York alone - it's a first chance to emerge from the shadows of American life, to replace daily fear with the refreshing breath of knowledge - often laced with a joke or two.

''Most have been in this country at least five years. All that time they've been in the shadows. For a lot of them this is a big opportunity - to learn English without being turned in,'' said Jim Roth, who trains amnesty teachers at CUNY.

By day, Evertz's students are factory workers, truck drivers, seamstresses. They came here from the Dominican Republic, Mexico, Colombia, Peru, Central America. At 6 p.m., they gather in a Spartan classroom in a converted trailer surrounded by coiled razor wire to learn English and American civics.

Such amnesty classes have been offered nationwide for the last two years at hundreds of community colleges, public schools, churches, charitable organizations and proprietary schools.

They exist for the 1.7 million formerly illegal aliens who came forward during the federal amnesty program that lasted for a year beginning May 4, 1987.

Those who revealed themselves gained temporary residence status and had 30 months to fulfill requirements for permanent status. Most amnesty classes will shut down around November, the deadline for most to fulfill their requirements for permanent status.

The requirements include either demonstrated competence in English and civics, or attendance at least 40 hours of amnesty classes.

Critics have cited the near-impossibility of teaching English in 40 hours. But officials of the Immigration and Naturalization Service, which administers the program, and teachers and pupils, think such criticism misses the point.

''Forty hours is not enough to learn English. We can all agree on that,'' said Janet Charney, deputy assistant commissioner of the legalization division of the INS in Washington. ''But the purpose was to get people indoctrinated into the culture, and help them gain some survival skills .. we have found that many have gone on to further study.''

The amnesty classes are ''an aperitif to show these people that they can learn,'' agreed Adolfo Calovini, a teacher at Hostos who speaks six languages and helped develop that school's amnesty curriculum.

The classes could hardly be described as rigorous, and the INS allows schools wide latitude in what should be taught.

Virtually everyone attending the necessary 40 hours will get a ''certificate of satisfactory pursuit'' required to go from temporary to permanent residence status.

The first weeks of the course are spent teaching students English phrases needed for everyday life, ''my name is...'', ''I live at...'', and survival skills like handling telephone conversations.

After about twenty hours, the course tackles civics. At Hostos, teachers talk about the history and significance of national holidays like July 4th, Columbus Day and Martin Luther King's birthday.

Eventually, the classes will study the basics of the Constitution, the Bill of Rights, and features of government.

Roberto Flores, a beer truck driver with a wife and son who crossed the Mexican border illegally in 1981, said he is no longer afraid about his immigrant status.

''It's a very good class. In my job, I must speak English and this helps me,'' he said.

But as relaxed as Evertz tries to make his class, fear lingers among immigrants still unaccustomed to dealing with official institutions.

Several in Evertz's class looked worried one evening as a reporter scribbled notes and a photographer clicked off shots.

''Don't worry, they're not agents. They're from the TV show, 'Lives of the Rich & Famous,'' said Evertz, as his studnts laughed again.