The World Health Organization, the United Nations health agency, uses a system of six phases to warn of possible influenza pandemics.

VOA: special.2009.05.06

However,the national social security law established a system that would grow and become a central part of American life.

VOA: special.2011.04.07

Much harder,of course, is changing a system that let companies take the risks that led to the current financial crisis.

VOA: special.2009.03.20

He had a system. He would describe characters and plots, then have ghostwriters expand those ideas into a book.

VOA: special.2009.08.24

They used a system of measurement called the Body Mass Index to define words like obese and overweight.

VOA: special.2009.07.21

Google has invested in a new company that wants to put up a system of satellites over Africa.

VOA: special.2009.02.16

They are making their way up a system built years ago to link the Mississippi to Lake Michigan.

VOA: special.2009.12.15

Professor Gaechter says social order in general can be explained as a system in which individuals behave cooperatively and follow social rules.

VOA: special.2009.03.03

But he hopes to raise billions through a system in which businesses that release greenhouse gases would buy and trade pollution permits.

VOA: special.2009.02.27

One showed that adults are much more cooperative if they work in a system based on rewards.

VOA: special.2009.10.21

Ted Fujita was a weather expert who developed a system to rate tornados in the nineteen seventies.

VOA: special.2011.04.19

In such a system,he said, the minority would be able to veto actions of the majority.

VOA: special.2009.04.02

She said the new law will reward quality over quantity of care, creating a system that prevents diseases before more costly treatment is required.

VOA: special.2010.04.21

Google agreed to create a system to pay copyright holders when their works are used online.

VOA: special.2011.04.01