Comparing Pro Bono with three current volunteer service models, I find out these features of Pro Bono:Pro Bono is based on professional skill and professional responsibility, it's more professional;

与当前国内三种主要志愿服务模式相比，专业志愿服务的特征突出表现为：以职业技能为基础，突出专业性；

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The famous Irish singer Bono from the group U2 also performs on this song.

VOA: special.2009.07.31

Through collaborations with U2's Bono on the single "In A Lifetime" and a series of further album successes they became one of the best-selling exponents of the Celtic music phenomenon the world has seen.

CNN: WorldBeat Spotlight - World's playing along with frenzied fiddlers of Celtic music

On August 4, the American Center for Law and Justice filed a pro-bono lawsuit on behalf of firefighter and first responder Tim Brown, a founder of the Coalition.

CENTERFORSECURITYPOLICY: Investigating America

In a press conference after his stage talk, Bono elaborated on the next stage of the poverty fight.

FORBES: Bono's Breaking News: Seven Thousand Children Are Not Dying Every Day