The U.S. House of Representatives voted by a large majority to pass a bill.

The bill makes daylight saving time permanent.

The Senate must still pass it before it can become law.

President Donald Trump has said he supports it.

The bill would end the twice-yearly clock change in spring and fall.

An AP-NORC poll last year found only 12% of American adults liked the current system.

Almost half of them opposed it.

Supporters of one time include the American Medical Association and the American Academy of Sleep Medicine.

America tried permanent daylight saving time before, in the 1970s.

Congress passed a law in 1973 for a trial from January 1974 to April 1975.

It lasted only until October 1974.

Public outcry led to its repeal.

A big concern was that schoolchildren would have to go to school in darkness.

Kevin Birth, a professor at Queens College, remembers the experience clearly.

He said it was "pitch black" into the school day.

Birth said more than just clocks must change if the U.S. tries again.

The current four time zones would need changes.

Sunrise times vary greatly within each zone.