alertness

/əˈlɜːtnəs/ (bre, ipa) · /əˈlɜːrtnəs/ (ame, ipa) · /ə-ˈlərt-nəs/ (ame, mw)

alertness — noun

1. a condition in which someone is mentally prepared to notice change and react qui

1.名詞C1
釋義

a condition in which someone is mentally prepared to notice change and react quickly if something happens

例句

The nurse's alertness helped her notice the patient's breathing change at once.

alertness helps someone notice danger quickly

Night drivers need constant alertness on roads with sudden fog.

constant alertness in changing road conditions

同義詞
  • vigilance

    suggests more sustained and careful watching, especially for danger

  • readiness

    focuses on being prepared to act, with less emphasis on noticing details

  • watchfulness

    stresses keeping your eyes on people or events over time

反義詞
  • drowsiness

    suggests reduced wakefulness and slow reactions

  • carelessness

    focuses on failing to pay enough attention

文法句型

maintain alertness

need alertness

用法筆記

Often used for a person's or group's state during work, travel, or emergencies. Distinguish from sense 2: sense 1 is a temporary state in a situation, not a person's general mental sharpness.

常見錯誤

❌Night workers need a lot of alertnesses.
✅Night workers need a lot of alertness.
💡'Alertness' is normally uncountable, so do not add a plural ending.

2. the ability to spot small details fast and think clearly enough to respond at on

2.名詞C1
釋義

the ability to spot small details fast and think clearly enough to respond at once

例句

Karim's alertness saved the team when he noticed the missing rope.

alertness in noticing a key detail quickly

The chess coach admired Nora's alertness during the fast final round.

同義詞
  • quick thinking

    focuses more on making a fast decision than on noticing details

  • presence of mind

    emphasizes staying calm enough to act well in pressure

  • attentiveness

    suggests careful attention, but not always the same speed of reaction

反義詞
  • slowness

    suggests delayed thought or reaction

  • confusion

    focuses on not noticing or processing events clearly

文法句型

show alertness

someone's alertness

用法筆記

Distinguish from sense 1: sense 2 focuses on a person's sharp mind and quick noticing, while sense 1 is the state of staying ready in a particular situation.

3. careful awareness of risks or warning signs, especially when trouble may be near

3.名詞C1
釋義

careful awareness of risks or warning signs, especially when trouble may be near

例句

The campaign raised parents' alertness to unsafe toys sold online.

alertness to + risk

After the flood, local alertness to river levels stayed high for months.

同義詞
  • awareness

    broader and less strongly focused on danger

  • caution

    emphasizes careful behavior rather than simple noticing

  • vigilance

    suggests longer and more active watching for threats

反義詞
  • indifference

    shows a lack of concern about a possible problem

  • complacency

    suggests feeling too safe and not noticing warning signs

文法句型

alertness to + noun

raise alertness to + noun

用法筆記

Usually followed by to when the focus is a danger, problem, or warning sign. Distinguish from sense 1: sense 3 is awareness of a specific risk, not general readiness to act.

常見錯誤

❌The posters increased alertness for pickpockets.
✅The posters increased alertness to pickpockets.
💡Use 'to' when naming the danger or problem people are being warned about.