1）volunteered to do sth.例：She volunteered to teach in the school.她自愿在学校教书。2）of on's own accord例：On her mother's birthday, Betsy did the housework of her own accord.母亲过生日那天，贝茜主动做家务。3）of one's own free will例：We should observe all regulations of our own free will.我们应该自觉遵守各项规定。
