What was going on when I was born?

New York City is considering an $8 million contribution to the Metropolitan Museum of Art to construct its long-planned southwest wing. The wing would be built over the museum's public parking garage and would not encroach on Central Park. The $8 million, if approved, would be the largest of the capital grants given to the Met by the city for the museum's master-building plan. It would complete a financing package about which Met officials say they have the ''lion's share'' from a private donor.

An off-duty Transit Authority police officer was shot to death in the Bronx last night in a confrontation with two New York City police detectives that began with a dispute over traffic. The officer, 40-year-old Thomas Johnson, who had been with the transit police for 13 years, died at Lincoln Hospital early today after undergoing two and a half hours of surgery for a bullet wound in the neck, according to David Vickers, an administrator at the hospital. Sgt. Ed Burns of the Police Department gave the following account of the incident: At about 7 P.M. the two city detectives, Lloyd Wilson and Hugh Clark, who are assigned to the 40th Precinct detective unit in the Bronx, were driving a witness home in an unmarked police car. As they were driving up Cauldwell Avenue, a one-way street in the Melrose section, they encountered a truck between 158th and 156th Streets traveling in the wrong direction.

A witness in a Federal fraud investigation was found shot to death yesterday, and the police said she had probably been slain by the same gunman who killed three CBS employees Monday when they apparently went to her aid in a parking lot on Manhattan's West Side. Detectives said they believed that the man had stalked the murdered woman, Margaret Barbera, and that he was a professional killer. They also said her murder might be related to a Federal investigation into the embezzlement of about $6 million from a Manhattan diamond company. Another woman, Jenny Soo Chin, a friend and former co-worker of Miss Barbera, disappeared last January, and the police fear she also may have been killed. Woman Had Pleaded Guilty Miss Barbera, who was 38 years old and lived at 613 Grandview Avenue in Ridgewood, Queens, was found, shot in the back of the head, in an alley in lower Manhattan. She had pleaded guilty on March 29 to Federal conspiracy charges involving fraud and, according to court records, had agreed to cooperate with the United States Attorney's office in Manhattan in a continuing inquiry.

* Nan Bedford and May Lou Gorno have been elected partners of Tatham-Laird & Kudner Advertising, Chicago. * Cintra H. Huber has been appointed vice president of marketing for Phillips International, the auctioneer.

After raucous debate, a City Council committee yesterday approved new boundary lines for 35 Council districts. Council leaders hope the action, by the Committee on Rules, Privileges and Elections, will permit elections to be held in November. The 9-to-1 vote approving the lines, which came at 5:30 P.M., means the plan can be considered by the full Council at its next meeting, on April 27. Council leaders consider passage a virtual certainty. A meeting of the full Council yesterday could not consider the new lines because of a requirement that the bill ''age'' for eight days.

IN other, simpler times it was sufficiently satisfying for a horseplayer to have a successful, and therefore guiltless, day at the races, with success measured by whether the bettor won or at least broke even after an eight-race card. Horseplayers were single-minded people who went out to the track to bet, not to socialize, not to look at shrubbery, not to enjoy the air. If they ate at all it was on the run between races, and the fare usually consisted of sandwiches, hot dogs, hamburgers, snacks, coffee and doughnuts. The idea of eating bouillabaisse or a Linzer torte along about midcard would have been dismissed as so much gastronomic frippery. As would have Canadian bacon and shirred eggs with timed morning workouts, braised short ribs and buttered noodles with the daily double or whole suckling pig with the trifecta selections.

Many Americans who once spent hours discussing the merits of nouvelle cuisine now seem to be approaching food from a new point of view - as health-food gourmands. They are seeking out the best butter from Normandy or Denmark or Germany and the richest, creamiest goat cheeses with the highest butterfat content, but only if they are ''all natural,'' ''preservative- and additive-free.'' Nowhere was this strange marriage more evident than on a recent trip to California, where the most talked-about cooking is likely to feature a chicken grown without hormones that is smothered in a sauce made with creme fraiche, though the sauce is often served on the side. What California food-shop owners and restaurant chefs who prepare and sell this ''pure'' self-indulgent food say about their clienteles is being repeated all over the country on a smaller scale. ''Californians buy lots of butter and lots of greens,'' said Clark Wolf, manager of the Oakville Grocery in San Francisco, which is a cross between Dean & DeLuca and Balducci's in New York City.

Corregidor brings painful memories for veterans of 3 nations A2 Posters in Poland may signal new assault on Solidarity A3 Inquest into South African unionist's death focuses on affidavit A3 Around the World A7 Boy, 8 years old, killed in Gaza Strip protest A9 Moslem nations denounce Israel at the U.N. A11 Mitterrand to raise trade issues during visit to Japan A16 Government/Politics Ex-aide says tuition tax credit won't pass this year B5 Washington Talk Briefing A20 Required Reading A20 Whistle-blower at the Environmental Protection Agency A20 Republicans worry about eroding black support A20 General Around the Nation A18 Eight of first 13 black Navy officers have reunion at sea A18 Industry/Labor Strike shuts down Burlington Northern railroad A18 Education/Welfare Four nuns lose lawsuit in effort to regain teaching jobs A19 Features/Notes Man in the News: John F. Woodward, British admiral A14 About New York B3 Notes on People B4 Sports People B11 Going Out Guide C19 News Analysis David K. Shipler examines Israeli strategy on two fronts A1 Living Section Food Successes in food packaging: one new look - plain and simple C1 Eclectic cooking: wholesomeness fit for the gourmand C1 For horseplayers who care to eat, the card includes a menu C1 In the lore of Barbados, redistilled rum C3 The 60-Minute Gourmet: shad with roe and mushrooms C3 Another rise expected soon in the price of peanut butter C7 Wine Talk: declining franc means bargains in wines C13 Living Metropolitan Diary C2 Kitchen Equipment: classic molds for pate C2 Mrs. Herbst's, known for its strudel, is closing C9 Personal Health: Heart panel urges more prudent diet C10 New Yorkers, etc. C14 Arts/Entertainment ABC takes most Emmys in docu- mentary programming C15 Jim Sheridan presents ''Waiting for Beckett'' C15 Arrigo Boito's opera ''Nerone'' is revived C17 Segovia conducts first New York master class C17 Leaders in arts decry Federal budget cuts C17 Rock guitarist, Adrian Belew, issuing first solo album C20 Talking Heads sum up their sounds in new album C20 Kenneth Clark's ''Moments of Vi- sion'' reviewed C21 Muir Quartet and Sara Bloom, oboe, give recital C22 Lynn Redgrave in new comedy series ''Teacher Only'' C22 Sports N.F.L. players union breaks off contract talks B8 Ira Berkow on an original Met 20 years later B8 Brewers defeat Indians, 9-8, in 10 innings B8 40,845 see Mets beat Carlton, 5-2, in home opener B9 Quotation of the Day Editorials/Letters/Op-Ed Editorials A22 Tax all oil, and natural gas too Private school aid: a bad idea Bombs, cells and symbols Letters A22 Russell Baker: banning the only gentleman A23 James Reston: who's in charge here? A23 William J. Olson: if Iran defeats Iraq A23 Melvin A. Brenner: recontrol air fares A23

Prime Minister Menachem Begin has embarked on a strategy of brinkmanship, both in the process of peace with Egypt and the prospect of war with the Palestine Liberation Organization in southern Lebanon. Pressures are building in his Government for tough action on both fronts: postponing the April 25 withdrawal from Sinai and invading Lebanon. So far, the Prime Minister has withstood the angry and fearful counsel of some of his Cabinet members, turning their anxiety to some advantage in a complex diplomatic game. But there is some question about his ability or willingness to contain the boiling emotions of his countrymen, especially on the issue of Sinai.

The Reagan Administration announced today that it was going ahead with the sale of $60 million in military spare parts to Taiwan despite Peking's warnings that this could lead to a "retrogression" in Chinese-American relations. There was considerable uncertainty within the Administration on what Peking would do about the development, which has been pending for several months as Peking and Washington discussed but did not resolve the question of American military sales to Taiwan. "We have some experts who believe that china may grumble but in the end do nothing to set back relations," one Administration official said. "But there are others who say that they would not be surprised if China degraded relations by pulling back ambassadors."

A dispatch from Jerusalem Nov. 8 on the authorship of the Book of Gene- sis incorrectly reported two state- ments by Moshe Weinfeld, professor of biblical studies at Hebrew Universi- ty. He said that Julius Wellhausen, a 19th-century German Protestant theologian, had hypothesized that cer- tain chapters were written in fifth cen- tury B.C. In a study of the Book of Deuteronomy, Professor Weinfeld argued that two groups of authors were active at the same time, one of whom may have written Deuter- onomy and the other the Books of Le- viticus and Numbers.

Kenyon & Eckhardt's outpost in Boston, the heart of high tech country, has just picked up three pieces of business with collective billings of $2.5 million to $3 million.