What was going on when I was born?

The Argentine Government, in an accounting today of its war against leftist terrorism in the 1970's, justified the actions that led to the disappearance of thousands of people as legal and necessary to defend the nation. The long-awaited accounting, however, fell far short of the demands by human rights leaders and opposition politicians for details about what happened to those who disappeared and how many there were. The statement said the Interior Ministry would issue a list of all the requests about missing people that it has received since 1974 and would indicate which cases had been solved. News reports said the list would be made public Friday.

THIS weekend it might be wise to follow the lead of the tigers and elephants at the Bronx Zoo's Wild Asia. After having been cooped up for months in their winter cages, the animals will again roam free in their sprawling outdoor habitat, beginning tomorrow. For humans, too, this weekend can be a time to get reacquainted with the outdoors. In New York City and the suburbs, dozens of outside events beckon. There are organized walks and house tours, nature strolls and plant sales, a Fifth Avenue parade and an open-air train to see the animals at Wild Asia. James G. Doherty, the zoo's general curator, said this is the best time for visiting Wild Asia. ''The animals are a lot more active in the spring,'' he said. ''They are racing about and happy to be outside again.'' A newcomer has joined the ''Wild Asians.'' He is Zachary, a baby camel, who makes his public debut tomorrow. The Bronx Zoo is open from 10 A.M. to 5 P.M. daily, until 5:30 P.M. on Sundays. Admission on weekends is $2.50; $1 for children. The Bengali Express, the train that meanders through Wild Asia, costs $1.25 more; 75 cents for children. The number for information is 367-1010.

Over the objections of a dissident stockholder group, Jesse Werner, the longtime chairman of the GAF Corporation, managed today to extend for more than two weeks the voting on a resolution that might oust him. Mr. Werner announced from the podium that he and the other directors had decided to keep the polls open until May 13. Half-a-dozen shareholders jumped to their feet in protest. ''I've never seen anything like this in all the meetings I've attended,'' shouted John Gilbert, who attends the annual meetings of many corporations, usually as a gadfly, although he said he was neutral in this dispute. Mr. Gilbert questioned the legality of changing the voting rules.

Nine present and former police officers, a former sanitation police lieutenant and a former firefighter were charged yesterday with crimes involving payoffs from illegal after-hours clubs in Manhattan. The charges grew out of an 18-month F.B.I. undercover investigation into suspected police corruption and centered on clubs in the Chelsea section of Manhattan and on East 14th Street, mainly during 1981 and 1982. The total payoffs to each, according to the charges, ranged from $300 to $5,000. Authorities said the payments had been made so the officers would overlook the illegal sale of liquor, double-parking outside the clubs and complaints by club patrons.

International The Common Market expressed ''deep concern'' over Reagan plans to tighten curbs on East-West trade. The memorandum delivered in Washington underscores Europe's resentment over proposed changes in the Export Administration Act that would authorize a ban on American imports from nations that sell to the Communist bloc in violation of U.S. trade sanctions. (Page A1.) Paul A. Volcker said he favors limited intervention in foreign exchange markets ''when exchange rates seem clearly wrong.'' The Federal Reserve chairman's statements appeared to go beyond Administration policy on the issue. (D1.)

Delta Air Lines reported yesterday that its loss for the first quarter widened substantially. United Airlines and Air Florida both reported that their deficits had narrowed for the period, although the levels remained substantial. All three carriers attributed the persistent deficits to heavy discounting of fares, which offset strong growth in traffic in the latter part of the quarter. But the carriers said they expected conditions to improve in the second quarter as discounting gives way to a new mileage-based fare structure that went into effect late this month.

An article March 29 on a symposium in Middletown, Pa., incorrectly described the 1979 accident at the Three Mile Island nuclear power plant. The pressure-relief valve of the reactor did not spout radioactive steam into the atmosphere.

International Richard B. Stone was appointed Ambassador at Large to Central America by President Reagan. The appointment of Mr. Stone, a conservative Democrat and former Senator from Florida, prompted some criticism because of his former role as a registered agent for the right-wing Government of Guatemala. (Page A1, Col. 4.) Nicaragua again requested talks with the United States over differences. In an interview, the Foreign Minister accused President Reagan of ''working on the fears of the American people'' with ''absurd and deceitful charges against Nicaragua.'' (A8:3-4.)

President Reagan today named former Senator Richard B. Stone, a conservative Democrat, as his Ambassador at Large for Central America, as Congressional Democrats reacted cautiously to Mr. Reagan's appeal for bipartisan support of his policy for the region. Mr. Reagan .gained postponement of a scheduled vote in the House Intelligence Committee on a proposal to halt covert operations financed by the Central Intelligence Agency in Nicaragua. But the committee chairman, Edward P. Boland, said he had ''sufficient votes'' to adopt the ban next week. Other House and Senate Democratic leaders forecast that Mr. Reagan would get only part of the $110 million in extra military aid he requested for El Salvador this year. Although Republicans talked of fairly quick action, key Democrats saw no urgency after what they described as a fairly sluggish public reaction to the President's speech.

The General Motors Corporation's two main American competitors came forward with strong antitrust objections today to G.M.'s plan to join with the Toyota Motor Corporation to produce a variant of Toyota's subcompact Corolla car in California. The Chrysler Corporation and the Ford Motor Company, intensifying their efforts against the deal, said the Federal Trade Commission should declare that the plan violates the Clayton Act and other antitrust statutes. The Clayton Act prohibits acquisitions that substantially reduce competition. Ford's vice president, David N. McCammon, told a House subcommittee inquiring into the international competitiveness of the United States that the deal between the world's No.1 and No.3 auto makers would eliminate competition between them in small cars. This, Ford said, would allow G.M. to devote more of its resources to the market for large cars, ''where it already accounts for a dominant two-thirds'' of the American market.

IN recent years, there has been a revival of interest in medieval and Renaissance music. Gone are the days when college textbooks condensed all composers before Bach into one opening chapter. Now early-music performance groups abound, their recordings sell briskly and when they peform, concerts halls are filled with rapturous listeners. Some of the sounds are so fresh and daring - the radical harmonies of Don Carlo Gesualdo's madrigals, the brimming passion of Monteverdi's operas - that they appeal to us with the urgency of our contemporaries.

The Scouting column in Sports Pages on Tuesday incorrectly described the yacht Azzurra and her display tomorrow in Providence, R.I. Azzurra's challenge to the America's Cup is sponsored by an Italian consortium with the Aga Khan as its principal organizer, but she is not his personal yacht. She will be on display alone, unaccompanied by Shabaz, which he owns.