1 [I,T] volunteer (sth);volunteer (to do sth) to offer sth or to do sth which you do not have to do or for which you will not be paid 自愿地或无偿地做或提供 · They volunteered their services free. 他们自愿提供免费服务。She frequently volunteers for extra work because she really likes her job. 她常常自发做额外工作，因为她真的喜欢她的工作。One of my friends volunteered to take us all in his car. 我的一个朋友自愿让我们都搭他的车去。

2 [I] volunteer (for sth) to join the armed forces without being ordered 志愿入伍

3 [T] to give information, etc or to make a comment or suggestion without being asked to 主动提供消息、发表意见或提出建议: I volunteered a few helpful suggestions. 我主动提出了一些有用的建议。