This is because glass has the hardness of crystal materials while also having a disordered arrangement of molecules like a liquid.

VOA: special.2009.09.16

Buddy Holly was killed in the crash of a small plane while on a singing tour in the Midwest.

VOA: special.2009.04.06

One description said it was like sitting in the driver's seat of a small car, while wearing two heavy raincoats.

VOA: special.2009.06.17

But it is only a beginning. John Kress of the Smithsonian says that, while science accepts evolution, debate continues.

VOA: special.2009.12.01

He set a time limit for withdrawal of most American troops from Iraq, while increasing the number of troops in Afghanistan.

VOA: special.2009.05.02

It held for a while. Then Union soldiers acting without orders forced their way to the top of the hill.

VOA: special.2009.11.26

The researchers left a piece of paper on the handlebars of the bicycles while their owners were away.

VOA: special.2009.03.03

For a while, they settled in the state of Illinois, in a town they built and called Nauvoo.

VOA: special.2009.06.04

While there, he volunteered as a music teacher at a youth center in the Dorchester neighborhood of Boston.

VOA: special.2010.11.04

Many of his stories are about a child trying to survive while facing difficult emotions such as fear.

VOA: special.2009.10.05

He tried to show that his Democratic Party was a national party, while the Republican Party was a party only of the North.

VOA: special.2009.06.11

The highest point of the softly curved hill measures about three meters tall, while the lowest point is only a few centimeters thick.

VOA: special.2009.05.06

It provides a continuous flow of air into the throat and lungs while the person sleeps.

VOA: special.2011.05.04

There are four kinds of echidnas: three species are long-nosed, while another has a short nose.

VOA: special.2009.07.07