As soon as the tremor passed, many people spontaneously arose and cheered.
震感刚一过去,很多人就自发地站起来欢呼。
He was never spontaneously warm or friendly towards us.
他从未自然而然地对我们表示过热情或友好。
2ADJ 自然的,自发的(指由于内部原因而非外界影响所引起的) A spontaneous event happens because of processes within something rather than being caused by things outside it. 自然的,自发的(指由于内部原因而非外界影响所引起的)
I had another spontaneous miscarriage at around the 16th to 18th week.
我在大约第 16 至 18 孕周时又经历了一次自然流产。
...a spontaneous explosion.
自爆
spontaneously
Usually a woman's breasts produce milk spontaneously after the birth.