uncertain

uncertain — 形容詞

1. feeling doubt or hesitation about what to do, believe, or choose, especially whe

1.形容詞B1
釋義

猶豫；遲疑

對某件事無法確定或下決定

feeling doubt or hesitation about what to do, believe, or choose, especially when the right decision is not yet clear to you.

例句

Eri was uncertain whether to take the job in Taipei or stay home.

Eri 不確定是否要接受臺北的工作機會，還是留在家鄉。

be uncertain whether + to-infinitive

The committee remained uncertain about how to fund the new library in the district.

委員會對於如何資助區內的新圖書館仍然猶豫不決。

remain uncertain about + noun phrase

同義詞
  • unsure

    more common in everyday speech; less formal than uncertain

  • hesitant

    focuses on the delay or reluctance to act, not just the mental doubt

  • doubtful

    implies a stronger leaning toward one side being unlikely

  • undecided

    specifically about a choice between options, not about beliefs

反義詞
  • certain

    the direct opposite; having no doubt

  • sure

    more informal and commonly used in everyday conversation

文法句型

be uncertain about + noun/gerund

be uncertain whether + to-infinitive

feel uncertain of + noun

remain uncertain about + wh-clause

用法筆記

Predicative only — this sense of uncertain never appears directly before a noun. Use “a confused decision” or “a doubtful look” instead of “an uncertain decision” when describing the decision itself.

常見錯誤

❌I am uncertain person about the plan.
✅I am uncertain about the plan.
💡uncertain in this sense is predicative and cannot modify a noun directly.
❌She is uncertain to come to the party.
✅She is uncertain whether to come to the party.
💡use whether (not to) to express indecision about an action.

2. not yet decided, confirmed, or clearly known — the details, outcome, or facts of

2.形容詞B1
釋義

未定；不明

尚未知道結果或尚未被確認的

not yet decided, confirmed, or clearly known — the details, outcome, or facts of a situation are still open or not firmly established.

例句

The cause of the fire remains uncertain even after months of investigation by experts.

即使經過專家數月的調查，火災原因仍然不明。

remain uncertain (predicative, subject = fact)

It is still uncertain whether the music festival will go ahead despite the storm damage.

音樂節是否能在風暴造成的損害後如期舉行，目前仍不確定。

it is uncertain whether + clause

同義詞
  • unclear

    focuses on lack of clarity; more neutral tone

  • vague

    suggests the information itself is imprecise or poorly defined

  • indefinite

    implies no fixed limits or deadlines have been set

  • unresolved

    suggests an issue that remains open and needs to be settled

反義詞
  • certain

    something that is known or fixed without doubt

  • decided

    a matter or outcome that has been settled

文法句型

something is uncertain

it is uncertain whether / if / when…

remain uncertain

uncertain + noun (attributive)

用法筆記

Unlike sense 1 (NOT SURE), this sense works both predicatively and attributively. When used before a noun, it describes something whose outcome or nature is unknown: “uncertain future,” “uncertain outcome.” Frequently used in academic and journalistic writing with dummy-it structures.

3. likely to shift or change from one condition to another, especially in ways that

3.形容詞B2
釋義

易變；不穩

容易改變、難以預測或依賴的

likely to shift or change from one condition to another, especially in ways that are hard to predict or depend on.

例句

The weather in this mountain area is uncertain — storms can arrive without any warning.

這個山區的天氣很不穩定——暴風雨可能毫無預警地突然來襲。

uncertain weather (attributive describing unpredictable nature)

Otis's job situation has been uncertain ever since the company announced the layoffs last month.

自從公司上個月宣布裁員以來，Otis 的工作狀況一直很不穩定。

situation / future + be uncertain (predicative)

同義詞
  • unpredictable

    stronger emphasis on not being able to foresee what comes next

  • unstable

    suggests a tendency to change in a negative, disruptive way

  • variable

    more neutral and technical; used for measurable changes like temperature or speed

  • volatile

    stronger and more dramatic; implies sudden, extreme shifts

反義詞
  • stable

    not changing or likely to change; steady

  • constant

    continuing at the same level or rate without variation

  • reliable

    can be trusted to stay the same or perform dependably

文法句型

uncertain + noun (attributive)

become / grow uncertain

something is uncertain (predicative, describing changeable nature)

用法筆記

This sense overlaps with “unstable” but is broader — it covers any kind of unpredictable change (weather, prices, moods, political conditions), not just structural instability. When used predicatively, the subject is typically a condition or situation rather than a person.

常見錯誤

❌She is uncertain today because of the fight.' (when meaning moody)
✅Her mood is uncertain today because of stress.
💡this sense describes a condition, not a person's feelings.