Alert vs Fast on our feet

When to use each in English, with meaning, register, and examples.

Alert

Top 1,000 (very common)C1verb

Fast on our feet

Top 3,000 (common)
Most common: Alert
 AlertFast on our feet
Pronunciation🇬🇧 /["/əˈlɜːt/","/əˈlɜːts/","/əˈlɜːtɪd/","/əˈlɜːtɪŋ/"]/🇺🇸 /["/əˈlɜːrt/","/əˈlɜːrts/","/əˈlɜːrtɪd/","/əˈlɜːrtɪŋ/"]/🇬🇧 //fæst ɒn aʊər fiːt//🇺🇸 //fæst ɑn aʊər fit//
MeaningAware and paying attention; quick to notice things.able to move quickly or react quickly
ExampleNeighbours quickly alerted the emergency services.The dancer was fast on our feet, impressing everyone with her moves.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 3,000 (common)
CEFR levelC1-
Part of speechverb
Collocationsstay alert, alert to danger, make someone alert, be alert for signsbe fast on our feet, remain fast on our feet, get fast on our feet
Antonymsunaware, distracted, sleepy-
Common mistakes'Alert' used as a noun instead of an adjective., Confused with 'alarmed', which means frightened., Using 'alerts' incorrectly as a verb form.Confusing with 'fast on the ground' which is incorrect., Using inappropriately in contexts about speed without agility., Translating directly to other languages without understanding idiomatic usage.
Usage notesUse 'alert' to describe someone who is attentive. It can be used in formal and informal contexts, but avoid using it in very casual conversations.Used in both formal and informal settings; implies agility or quickness in response. Often positive in tone.

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Fast on our feet

Frequently asked questions: Alert vs Fast on our feet

What's the difference between Alert and Fast on our feet?

Alert: Aware and paying attention; quick to notice things. Fast on our feet: able to move quickly or react quickly

Which is more common: Alert and Fast on our feet?

Alert is the most common in everyday English.

Can you show an example of each?

Alert: Neighbours quickly alerted the emergency services. Fast on our feet: The dancer was fast on our feet, impressing everyone with her moves.

Can I use Alert and Fast on our feet interchangeably?

Not always. Alert and Fast on our feet are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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