Voluntary actions or activities are done because someone chooses to do them and not because they have been forced to do them.
近义词
optional
反义词
mandatory
双语例句
例：
Attention is drawn to a special voluntary course in Commercial French.
一门特别的商务法语选修课引起了大家的关注。
例：
The scheme, due to begin next month, will be voluntary.
此项目为自愿参加并将在下个月开始。
2.?义务的
Voluntary work is done by people who are not paid for it, but who do it because they want to do it.
近义词
charitable
反义词
paid
双语例句
例：
In her spare time she does voluntary work.
她利用业余时间做义工。
例：
He'd been working at the local hostel for homeless people on a voluntary basis.
他曾在当地的救助站做义工，帮助无家可归者。
3.?志愿的
A voluntary organization is controlled and organized by the people who have chosen to work for it, often without being paid, rather than receiving help or money from the government.
双语例句
例：
Some voluntary organizations run workshops for disabled people.