But he is hard at work. He and his team currently are trying to make algae that can change carbon dioxide back into fossil fuel.

VOA: special.2010.07.20

William Thornton is hard at work on a set of building drawings.

VOA: special.2010.01.27

These paintings show Americans hard at work in different industries.

VOA: special.2009.01.02

Many students work hard at summer jobs.

VOA: special.2010.06.18

The young people here are hard at play, and the Muslim elders are hard at work trying to keep them engaged in positive activities.

VOA: standard.2009.12.20

He says he learned playing basketball at Princeton University that both take hard work and perseverance.

VOA: standard.2010.06.24

"I think they have to have an example like some stars like Landon Donovan on the US national team of the World Cup so they can see what an example is and what they could be like when they grow up and work hard at football."

VOA: standard.2010.06.15