Copy that vs Understood vs Will do

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

Copy that

InformalTop 2,000 (common)

Understood

Top 1,000 (very common)

Will do

Most formal: UnderstoodMost common: Understood
 Copy thatUnderstoodWill do
Pronunciation🇬🇧 //ˈkɒpi θæt//🇺🇸 //ˈkɑpi θæt//🇬🇧 //ˌʌndəˈstʊd//🇺🇸 //ˌʌndərˈstʊd//
MeaningI understand you or I will do that.To know or comprehend something.
ExampleWhen you’re ready, just say 'copy that'.After the explanation, I finally understood the problem.-
RegisterInformalNeutral-
How commonTop 2,000 (common)Top 1,000 (very common)-
Collocationscopy that, over, copy that, roger, copy that, understoodfully understood, clearly understood, never understood, easily understood-
Antonymsignore that, disregard that, neglect thatmisunderstood, confused, ignorant-
Common mistakesUsing in formal contexts., Confusing with 'copy' as a verb., Not responding after saying 'copy that'.Confused with 'understand' in different tenses., Using 'understood' in present tense situations., Mispronouncing the word, leading to misunderstandings.-
Usage notesUsed to acknowledge understanding in casual conversations, often in radio communication. Avoid in formal writing or speeches.Use 'understood' in past tense contexts or when confirming comprehension. Avoid in formal writing where 'comprehended' may be preferred.-

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Copy that
Understood
Will do

Frequently asked questions: Copy that vs Understood vs Will do

What's the difference between Copy that, Understood, and Will do?

Copy that: I understand you or I will do that. Understood: To know or comprehend something. Will do:

Which is more formal: Copy that, Understood, and Will do?

Understood is the most formal of these.

Which is more common: Copy that, Understood, and Will do?

Understood is the most common in everyday English.

Can I use Copy that, Understood, and Will do interchangeably?

Not always. Copy that, Understood, and Will do 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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