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Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
you must know
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "you must know" is correct and usable in written English.
It can be used to emphasize the importance of a piece of information that the speaker believes the listener should be aware of. Example: "Before we proceed with the project, you must know the deadlines and requirements to ensure everything runs smoothly."
✓ Grammatically correct
News & Media
Academia
Wiki
Alternative expressions(20)
it is essential to know
it is important to understand
you need to understand
it should be noted that
bear in mind that
take note of
don't forget that
keep in mind that
you should be aware
you must discover
you must lose
you ought to know
you must study
you must integrate
you must complain
you must edit
you must chew
you must want
you need to know
you must go
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
60 human-written examples
"You must know that".
News & Media
You must know Mrs Carter?
News & Media
This you must know.
Academia
You must know that already.
News & Media
You must know Norman Shrapnel".
News & Media
You must know the answer".
News & Media
You must know about him".
News & Media
You must know where they lead.
News & Media
(It's Philip, if you must know).
News & Media
You must know how the sport works".
News & Media
It's hideous, if you must know.
News & Media
Expert writing Tips
Best practice
Use "you must know" to emphasize information that is crucial for your audience to understand, especially when setting context or explaining underlying assumptions.
Common error
Avoid using "you must know" excessively, as it can come across as condescending or patronizing. Vary your language by using alternatives like "it's important to understand" or "bear in mind that" to maintain a respectful tone.
Source & Trust
83%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "you must know" primarily functions as a directive, urging the listener or reader to acknowledge a piece of information deemed essential by the speaker. As seen in Ludwig examples, the phrase introduces context, background, or prerequisite knowledge. Ludwig AI confirms it is correct.
Frequent in
News & Media
52%
Wiki
23%
Academia
13%
Less common in
Science
7%
Formal & Business
4%
Reference
1%
Ludwig's WRAP-UP
The phrase "you must know" is a grammatically sound and frequently used expression to emphasize the importance of a piece of information. As Ludwig AI confirms, the phrase is suitable across varied contexts but predominantly appears in News & Media, Wiki, and Academic sources. While versatile, it’s crucial to avoid overuse to prevent sounding condescending; alternatives like "it's important to understand" offer a softer approach. Remember to use this phrase to highlight essential details or prerequisites, ensuring clarity and comprehension in your communication.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
it is essential to know
Emphasizes the necessity of knowledge, similar to "you must know", but with a slightly more formal tone.
it is important to understand
Focuses on comprehension rather than simple awareness, adding a layer of depth.
you need to understand
Highlights the requirement for understanding, shifting the emphasis to necessity.
it's crucial to realize
Emphasizes the critical nature of realization, often implying a potential consequence if not understood.
bear in mind that
Encourages the listener to remember a specific piece of information, framing it as a reminder.
take note of
Directs attention to a specific detail or fact, urging the listener to pay close attention.
it should be noted that
Introduces information that is significant and warrants attention, often in a formal context.
don't forget that
Serves as a reminder, useful when the information might be overlooked.
keep in mind that
Similar to "bear in mind", but slightly less formal, suggesting a continuous awareness.
you should be aware
Highlights the importance of being informed, setting a tone of caution or preparedness.
FAQs
How can I use "you must know" in a sentence?
You can use "you must know" to emphasize information that the listener should be aware of. For example, "Before we start, "you must know" the project's goals".
What can I say instead of "you must know"?
You can use alternatives like "it is essential to know", "it is important to understand", or "you need to understand" depending on the context.
Is "you must know" too informal for academic writing?
While "you must know" is acceptable, it might be more appropriate to use a more formal alternative in academic writing, such as "it should be noted that" or "it is important to understand".
What's the difference between "you must know" and "you should know"?
"You must know" implies a higher degree of necessity or importance than "you should know". "You should know" suggests that the information is helpful but not necessarily critical, while ""you must know"" indicates the information is essential.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
83%
Authority and reliability
4.5/5
Expert rating
Real-world application tested