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

VOA: special.2009.10.21

So they work well in places like electric motors in hybrid vehicles or generators for wind turbines.

VOA: special.2010.10.08

He says hand tools like tilling forks, shovels and thatching rakes require more work than a rotary tiller, but they work well and cost less.

VOA: special.2010.09.28

The volunteers learn about local culture and make friends as they work in the community.

VOA: special.2009.07.27

Some people may need to take medicines before they work hard or exercise.

VOA: special.2009.07.28

Experienced doctors who have treated many patients guide them as they work.

VOA: special.2009.06.02

They work for the American space agency's Jet Propulsion Laboratory in California.

VOA: special.2009.08.25

They work hard. They practice their singing in Mr.Cockrell's classes.

VOA: special.2011.04.01

They cannot support flight. But they work well for swimming.

VOA: special.2009.12.16

Because we think once we understand how they work, we could be able to manipulate the mosquito genetically and convert mosquitoes that can transmit malaria into mosquitoes that cannot transmit malaria."

VOA: special.2009.12.22

When they work together, chemical reactions take place smoothly.

VOA: special.2009.04.21

They work in Washington during the week.

VOA: special.2010.09.10

"They've been installed for the last almost 15 years now and tests show that they work very well."

VOA: standard.2010.08.05

Most journalists say they work with less fear than they did one year ago.

VOA: standard.2009.09.15