What was going on when I was born?

The Reagan Administration today postponed a planned announcement that the United States was resuming delivery of F-16 fighter-bombers to Israel. At the same time, without directly criticizing Israel, the Adminstration called for a cease-fire in the warfare across the Israeli-Lebanese border. The Administration's actions followed air strikes early today by Israeli jets against what Israel said were Palestine Liberation Organization facilities in Beirut and targets in southern Lebanon. The air action in Lebanon was the most severe since Israeli troops moved into the southern part of the country in 1978 and was the fifth Israeli raid in a week against Palestinian targets in Lebanon.

Two crowded ''sky bridges'' inside the lobby of the Hyatt Regency Hotel here collapsed tonight, killing at least 45 people and injuring about 145, according to the police and rescue workers. Four and a half hours after the disaster, with the ruins of the walkways remaining to be lifted from the floor, the authorities said the toll could go much higher once the debris was removed with heavy equipment sent to the scene. ''We have found six people still alive who are trapped between the two skywalks,'' said Sgt. Jim Treece, a spokesman for the Police Department. ''We still don't know how many people are trapped, but there were 1,500 people in the lobby when it happened, and God only knows how many are still in there.''

Wayne B. Williams, a 23-year-old music promoter and talent scout, was indicted today on charges of murdering two of the 28 young black people slain here in the last two years. A Fulton County grand jury charged Mr. Williams with murdering Nathaniel Cater, 27, ''by strangling and asphyxiating'' him. The Cater slaying, the last one to occur, is the case in which Mr. Williams was arrested last month. The grand jury also charged Mr. Williams with murdering 21-year-old Jimmy Ray Payne ''by asphyxiating him with objects and by means which are to the grand jury unknown.''

Voting for the first time by secret ballot, delegates to the emergency congress of the Polish Communist Party elected a new Central Committee today, sending some of the most prominent figures in the leadership down to defeat. Leaders of both liberal and conservative extremes among the 279 condidates were eliminated in the single-ballot vote for the 200 seats on the committee. The centrist position of Stanislaw Kania, the centrist position of Stanislaw triumphant, a strong indication that Mr. Kania will be re-elected as First Secretary by the entire congress. Challenger to Kania Loses Tadeusz Grabski, a conservative on the Politburo who had undertaken a challenge against Mr. Kania and was planning to oppose him for the party leadership, lost getting 899 votes.

As Israeli planes struck at Beirut today, further widening the war against Palestinian guerrillas, Prime Minister Menachem Begin announced that the guerrillas could no longer expect to hide amid civilian populations in Lebanon. The warning, contained in a statement issued from the Prime Minister's office, was intended to press Lebanese authorities to curb Palestinian military operations against Israel from Lebanese soil. The Israeli planes struck at what officials said were two Palestinian headquarters buildings in the center of Beirut. An Israeli military spokesman said offices of two organizations - Al Fatah and the Democratic Front for the Liberation of Palestine - were destroyed, but he said nothing of casualties. Reports from Lebanon described civilian casualties as heavy.

Israeli jets today bombed a densely populated area of Beirut containing Palestinian guerrilla headquarters and, in wide raids in southern Lebanon, knocked out three more bridges. Palestinian reports said the raids had left at least 123 dead and more than 550 wounded, most of them in the Lebanese capital. The Israeli attack here, centering on Rue Baghdadi in a section of predominantly Moslem west Beirut called Fakehani, came unexpectedly late this morning and did not last more than 20 minutes, according to witnesses, some of whom said both rockets and bombs had been used. The devastation was intense.

The Reagan Administration would reluctantly accept as part of the 1981 tax-relief bill an initiative to create automatic adjustments of the income tax to offset inflation, starting in 1985, a spokesman for Treasury Secretary Donald T. Regan said today. The spokesman, Marlin Fitzwater, said the Administration would prefer that Congress defer action on this provision, which the Senate approved last night, to a later tax bill. "But we wouldn't oppose it," Mr. Fitzwater said, adding that it would not prompt a Presidential veto. The so-called indexing measure, which would automatically lift both ends of a tax bracket as consumer prices rise, was proposed by Congressional Republicans. Despite the Administration's apparent flexibility on the indexing proposal, however, it remained doubtful tonight that the House of Representatives would adopt such a provision or accept the Senat Version in a House-Senate conference.

Despite the Reagan Administration statement yesterday stressing the importance of free elections in El Salvador, there is skepticism in many quarters here that such elections are possible. And church leaders and some foreign diplomats here still feel that any solution to the conflict must include negotiations with the leftist guerrillas, a course that Washington continues to rule out. ''How can there be elections?'' a business leader said recently. ''What are we going to do? Campaign with loudspeakers mounted on top of our armored cars?''

Two American warships rescued 39 people from a Greek tanker that caught fire in the Arabian Sea, a United States Embassy spokesman said today. There were no reported casualties among the crew of the tanker, the Irene Sincerity.

In the language of the people who live there, the village's name is said to mean ''a place of death.'' Recently it lived up to its reputation. One afternoon, a bolt of lightning struck the school at Biego in western Kenya, crackled around the classroom and killed 11 children. It was, villagers recounted, the sixth time in their memory that lightning had struck the school. That, they said, could be no coincidence. And their response to the disaster said much about that part of Africa that lies beyond the modernity introduced by recent history.

Eleven days after the burning and rioting began, acrid puffs still drift over the racially mixed Toxteth district. Bulldozers are leveling the rubble of about three dozen shops. ''Business as Usual'' signs hang on the plywood shields covering the storefronts on Lodge Lane. Yet, strikingly, the prevalent emotion among blacks and whites is pride. ''We showed them we were not going to put up with police abuse any longer,'' said Peter Bassey, a 32-year-old unemployed black who a week ago tried to explain the community's rage during a meeting with Prime Minister Margaret Thatcher. Mr. Bassey said he does not think he got his point across.

The Social Democratic Party, barely four months old, came within an ace last night of winning a by-election in a constituency where the Labor Party has reigned supreme since World War II. After years of speculation about a realignment of British politics, some politicians said this morning that it might lie just ahead. The election in Warrington seems to have marked the emergence of a new-style party, commanding broad support without a class or geographical base, dependent upon neither the trade unions nor the landed gentry, positioned squarely in the center and capable of damping the wild oscillations from left to right that have marked the postwar era. Roy Jenkins, a former minister in Labor governments, astounded himself and everyone else by taking 42 percent of the vote at Warrington.