We understand the term volunteering to include formal activity undertaken through public, private and voluntary organisations as well as informal community participation and campaigning.

志愿服务通常可理解为包括公共部门、私人志愿性组织等正式部门的志愿服务行为，和社区参与等非正式部门的志愿服务行为。

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And it is younger people aged 16-24 that are more likely to be involved in informal volunteering than any other age group.

BBC: NEWS | UK | Public volunteers at record level

Two out of three citizens (65.1 percent or 143.7 million Americans) engaged in informal volunteering by doing favors for and helping out their neighbors.

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