adj. 自发的，非筹划安排的；（程序，事件）自发的，自然的；（人）天真率直的；（生物）（机体活动）本能的
spontaneous combustion自燃
spontaneous emission[电磁学]自发发射
词根：spontaneous
adv.
spontaneously 自发地；自然地；不由自主地
n.
spontaneity 自发性；自然发生
spontaneousness 自然；任意
1.No wonder they feel looser, more spontaneous, perhaps more assertive or funnier or blunter, in the language they were reared in from childhood.
难怪他们会觉得自己的语言更松散、更自然，或许会觉得自己从小学会的语言更自信、更有趣或更直率。
2.That's our condition for spontaneous change.
这就是自发变化的条件。
3.The reaction is not spontaneous.
化学反应不是自然产生的。
4.This is our condition for spontaneous change.
这就是自发变化的条件。
5.The displays of art museums serve as a warning of what critical practices can emerge when spontaneous criticism is suppressed.
艺术博物馆的展览提醒我们，当自发的批评被压制时会有什么样的批评行为出现。
6.This is known as spontaneous recovery.
这种现象叫做自发恢复。
7.It was quite spontaneous.
这是一次自发的活动。
8.Speak your mind, open up and be as spontaneous as you can.
说出你的心里话，放开自己并尽可能是发自本能的。
9.And yet, these things are all spontaneous processes.
然而，这些过程都是自发进行的。