volunteer
自愿提供(时间、技能或信息,强调主动意愿)
contribute
贡献(提供有价值的东西,可时间/金钱/努力,无需强调「自愿」,更通用)
Over two hundred community members volunteered their time to restore the local nature reserve over three consecutive weekends.
超过两百名社区成员连续三个周末志愿奉献时间,修复当地自然保护区。
The tech company agreed to contribute both funding and technical expertise to the city's smart infrastructure project.
这家科技公司同意向城市智慧基础设施项目贡献资金和技术专长。