Alert vs That was the signal

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

Alert

Top 1,000 (very common)C1verb

That was the signal

Top 2,000 (common)
Most common: Alert
 AlertThat was the signal
Pronunciation🇬🇧 /["/əˈlɜːt/","/əˈlɜːts/","/əˈlɜːtɪd/","/əˈlɜːtɪŋ/"]/🇺🇸 /["/əˈlɜːrt/","/əˈlɜːrts/","/əˈlɜːrtɪd/","/əˈlɜːrtɪŋ/"]/🇬🇧 //ðæt wəz ðə ˈsɪɡnəl//🇺🇸 //ðæt wəz ðə ˈsɪɡnəl//
MeaningAware and paying attention; quick to notice things.A signal is a sign to do something.
ExampleNeighbours quickly alerted the emergency services.When the bell rang, that was the signal for everyone to start the exam.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 2,000 (common)
CEFR levelC1-
Part of speechverb
Collocationsstay alert, alert to danger, make someone alert, be alert for signsgive a signal, receive a signal, clear signal, signal to start, signal for help
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.Confused with 'sign'. 'Signal' is more specific., Using it in unrelated contexts, like referring to mere events., Overusing in casual conversations, it fits better in descriptive contexts.
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 contexts where a cue is given. It is appropriate in both informal and formal settings.

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That was the signal

Frequently asked questions: Alert vs That was the signal

What's the difference between Alert and That was the signal?

Alert: Aware and paying attention; quick to notice things. That was the signal: A signal is a sign to do something.

Which is more common: Alert and That was the signal?

Alert is the most common in everyday English.

Can you show an example of each?

Alert: Neighbours quickly alerted the emergency services. That was the signal: When the bell rang, that was the signal for everyone to start the exam.

Can I use Alert and That was the signal interchangeably?

Not always. Alert and That was the signal 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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