spontaneously

spontaneously — adverb

1. Done because of a sudden inner desire or natural feeling, without being arranged

1.副詞B2
釋義

Done because of a sudden inner desire or natural feeling, without being arranged, forced, or thought about beforehand.

例句

Tomás spontaneously decided to fly to Tokyo after spotting a cherry-blossom poster.

spontaneously + decide + to-infinitive

The crowd spontaneously burst into cheers when the final goal was scored.

同義詞
  • naturally

    broader; can describe an innate quality rather than a specific unplanned action

  • impulsively

    stronger; suggests acting without thinking at all, not just without prior planning

  • instinctively

    based on inborn instinct rather than a conscious feeling or choice

反義詞
  • deliberately

    implies careful thought and intention, the opposite of acting on impulse

  • premeditatedly

    formal; suggests the action was planned and considered in advance

文法句型

spontaneously + verb

verb + spontaneously

用法筆記

Common with verbs of decision, reaction, or group behaviour (decide, burst, start, laugh, form). Often describes positive, unforced human actions in social or emotional settings.

常見錯誤

❌The car spontaneously stopped in the middle of the road' (when you mean it stopped suddenly).
✅The car suddenly stopped in the middle of the road.
💡'spontaneously' implies an inner will or natural impulse; a machine does not act of its own accord.

2. In a way that happens by itself, without a clear or visible outside cause, trigg

2.副詞C1
釋義

In a way that happens by itself, without a clear or visible outside cause, trigger, or human effort.

例句

The rash on Maeve's arm appeared spontaneously — the doctors could not find a cause.

spontaneously + appear (medical context)

Under certain conditions, a chemical reaction begins spontaneously without any added heat.

spontaneously + begin (scientific process)

同義詞
  • automatically

    suggests a mechanical or programmed process, not necessarily a natural one

  • involuntarily

    implies the action happens without or against one's will, not simply without a cause

文法句型

spontaneously + verb

verb + spontaneously

用法筆記

Frequently used in scientific, medical, and physical contexts where no external trigger is visible. Common verbs include appear, occur, arise, begin, and grow. This sense does not describe human choices or social behaviour.

常見錯誤

❌He spontaneously found his keys under the sofa' (when you mean by chance).
✅He happened to find his keys under the sofa.
💡'spontaneously' describes a process coming from within, not an event caused by external chance.