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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
are the key
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "are the key" is correct and usable in written English.
You can use it to refer to the most important element in a situation. For example, you could say "Time and patience are the key to success."
✓ Grammatically correct
News & Media
Formal & Business
Academia
Wiki
Science
Alternative expressions(8)
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
Expectations are the key.
News & Media
Women are the key.
News & Media
Baby steps are the key.
News & Media
Here are the key points.
News & Media
Artists are the key.
News & Media
People are the key.
News & Media
"Short" and "survey" are the key words.
News & Media
"They are the key asset, above all".
News & Media
They are the key to defeating it.
News & Media
What are the key findings from 2014?
News & Media
Mr Murguía says jobs are the key.
News & Media
Expert writing Tips
Best practice
When using "are the key", ensure you clearly define what elements or factors constitute the key components. This provides clarity and strengthens your argument.
Common error
Avoid using "are the key" as a generic statement. Instead, be specific about why the elements you are describing are crucial. Provide evidence or reasoning to support your claim.
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "are the key" functions as a predicate nominative, identifying and emphasizing the most important elements or aspects within a given context. Ludwig AI confirms its grammatical correctness and widespread usage.
Frequent in
News & Media
51%
Formal & Business
14%
Academia
12%
Less common in
Wiki
11%
Science
8%
Reference
4%
Ludwig's WRAP-UP
The phrase "are the key" is a common and grammatically correct expression used to emphasize the importance of particular elements or factors. As Ludwig AI confirms, it is suitable for various contexts, ranging from news and media to formal business communications. The phrase functions as a predicate nominative and its primary purpose is to highlight crucial factors. When using "are the key", remember to be specific about what makes these elements so important, and avoid overuse without providing supporting context. Similar phrases include "are essential", "are crucial", and "are vital".
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
are essential
Replaces "key" with "essential", emphasizing the necessity of something.
are crucial
Substitutes "key" with "crucial", highlighting the critical importance of something.
are vital
Replaces "key" with "vital", stressing that something is necessary for success or survival.
are fundamental
Substitutes "key" with "fundamental", indicating that something forms a necessary base or core.
are paramount
Replaces "key" with "paramount", meaning something is of the highest importance.
are critical
Substitutes "key" with "critical", underscoring the decisive importance of something.
are central
Replaces "key" with "central", highlighting that something is located in the center and of main importance.
are significant
Substitutes "key" with "significant", conveying the importance of something.
are instrumental
Replaces "key" with "instrumental", indicating that something is important in causing something to happen.
are the solution
Expresses that something provides the means of solving a problem or dealing with a difficult situation.
FAQs
How can I use "are the key" in a sentence?
You can use "are the key" to emphasize the importance of certain elements. For instance, "Patience and persistence "are the key" to mastering a new skill."
What phrases are similar to "are the key"?
Similar phrases include "are essential", "are crucial", or "are vital", all indicating high importance.
Is it correct to say "is the key" instead of "are the key"?
The choice between "is the key" and "are the key" depends on whether you are referring to a singular or plural subject. Use "is the key" for a singular noun and "are the key" for plural nouns.
What's the difference between "are the key" and "are key"?
"Are the key" implies that the items mentioned are the most important or crucial ones. "Are key" simply suggests that the items are important, but not necessarily the most important.
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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
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested