Comprehend vs You know something

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

Comprehend

Top 3,000 (common)B1verb

You know something

Top 2,000 (common)
Most common: You know something
 ComprehendYou know something
Pronunciation🇬🇧 //kəmˈprɛhɛnd//🇺🇸 //kəmˈprɛhɛnd//🇬🇧 //juː nəʊ ˈsʌmθɪŋ//🇺🇸 //ju noʊ ˈsʌmθɪŋ//
MeaningTo understand something fully.You understand or are aware of something.
ExampleI cannot fully comprehend the complexities of this theory.You know something important about the project.
RegisterNeutralNeutral
How commonTop 3,000 (common)Top 2,000 (common)
CEFR levelB1-
Part of speechverb
Collocationscomprehend fully, struggle to comprehend, easily comprehend, hard to comprehend, fail to comprehendyou know what I mean, you know the truth, you know better
Antonymsmisunderstand, ignoreYou don't know, You have no idea
Common mistakesConfusing 'comprehend' with 'comprehensive', which means complete or thorough., Using 'comprehend' incorrectly with a subject (e.g., saying 'I comprehend' without an object).Using 'you know' too often in formal contexts., Confusing it with 'do you know' which asks a question., Omitting context when using it as a filler in conversation.
Usage notesUse 'comprehend' in more formal contexts, often in academic or literary discussions. In casual conversation, 'understand' is more common.Commonly used to confirm understanding or share knowledge. Can be informal or formal based on context. Usually not appropriate for very formal writing.

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You know something

Frequently asked questions: Comprehend vs You know something

What's the difference between Comprehend and You know something?

Comprehend: To understand something fully. You know something: You understand or are aware of something.

Which is more common: Comprehend and You know something?

You know something is the most common in everyday English.

Can you show an example of each?

Comprehend: I cannot fully comprehend the complexities of this theory. You know something: You know something important about the project.

Can I use Comprehend and You know something interchangeably?

Not always. Comprehend and You know something 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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