adv.自发，自然，自动，自然地

The party started spontaneously when everyone suddenly began dancing.
当大家突然开始跳舞时，聚会自然而然地开始了。
She spontaneously decided to take a road trip without any prior planning.
她一时兴起，没有任何事先计划就决定去公路旅行。
The applause erupted spontaneously from the audience, showing their appreciation.
掌声从观众中自然爆发出来，表达了他们的赞赏。
Spontaneous laughter filled the room as the comedian told a hilarious joke.
当喜剧演员讲了一个极好笑的笑话时，房间里充满了自发的笑声。
The protest was not planned; it happened spontaneously in response to the news.
抗议活动并非事先策划，而是对新闻的直接反应，自然发生的。
The idea for the novel came to her spontaneously during a morning walk.
写小说的灵感在她早晨散步时自然而然地涌现了出来。
Spontaneous combustion can occur when certain materials heat up to their ignition point.
当某些物质加热到其燃点时，可能会发生自燃现象。
He spontaneously offered to help me move the furniture, which was a huge relief.
他主动提出帮我搬家具，这让我大大松了一口气。
The discussion became very engaging as participants contributed thoughts spontaneously.
讨论变得非常引人入胜，因为参与者都自发地贡献了想法。
Her smile was so spontaneous and genuine that it immediately brightened up the room.
她的笑容自然而真挚，立刻让整个房间明亮起来。