Used and loved by millions
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
that's serious
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "that's serious" is correct and usable in written English.
You can use it to express that a situation or statement is significant or concerning. Example: "When I heard about the accident, I realized that's serious and we need to take action."
✓ Grammatically correct
News & Media
Wiki
Formal & Business
Alternative expressions(1)
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
"The moment there are civilians involved in the casualties, that's serious," said Dr. Omar Saleh, the health organization's emergency humanitarian action coordinator for Somalia.
News & Media
If somebody's coming to see me about something that's serious to him, I want to get the background about him and about the issue".
News & Media
So I don't want to be glib about something that's serious.
News & Media
"It's nothing that's serious to where I would not be playing".
News & Media
Even after deducting the considerable costs of a running a big hedge fund, that's serious moolah.
News & Media
If you're a young pianist struggling to pay the rent, that's serious money.
News & Media
In the process, they came up with an agenda that's serious, detailed and mostly cogent.
News & Media
Wood responded by fashioning a critical voice that's serious but opinionated, heavily stylised but not slick.
News & Media
Ghent is a city that's serious about style, so of course it takes the B&B concept to another level.
News & Media
For any of those models, that's serious cash for a compact S.U.V.; a Toyota RAV4 V-6 with leather, navigation and all the toys is $33,000.
News & Media
"Anytime you've got a businessman who's engaged in munitions sales to a country that has been deemed a state sponsor of terrorism, that's serious," Mr. Arruda said.
News & Media
Expert writing Tips
Best practice
When aiming for more formal language, consider alternatives like "that is a grave matter" or "that is a significant concern".
Common error
While acceptable, avoid using "that's serious" excessively in highly formal or academic writing. Opt for alternatives with a more refined tone to suit the context.
Source & Trust
85%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "that's serious" primarily functions as an expressive interjection or declarative statement. It conveys the speaker's assessment of a situation, emphasizing its gravity or significance. This is confirmed by Ludwig AI, which indicates the phrase is grammatically correct and widely used.
Frequent in
News & Media
65%
Wiki
15%
Formal & Business
10%
Less common in
Academia
3%
Science
3%
Encyclopedias
2%
Ludwig's WRAP-UP
In summary, "that's serious" is a common and grammatically correct phrase used to express the gravity or significance of a situation. According to Ludwig AI, the phrase is usable in written English to express that a situation or statement is significant or concerning. While the phrase is suitable for a wide range of contexts, it is most frequently found in news and media, reflecting its utility in conveying important information swiftly. For formal settings, you may consider alternatives like "that is a grave matter" or "that is a significant concern" to maintain a refined tone. When using the phrase, remember it serves to prompt action or emphasize the importance of the matter at hand.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
that's a grave matter
Emphasizes the solemn and concerning nature of a situation.
that's a critical situation
Highlights the urgency and importance of addressing the situation.
that's a significant problem
Underscores the importance and potential impact of the issue.
that's a weighty concern
Highlights the seriousness and potential consequences of the issue.
that's cause for alarm
Indicates that the situation warrants concern and immediate attention.
that's nothing to scoff at
Highlights the need to take the situation seriously and avoid dismissiveness.
that's a major crisis
Emphasizes the scale and severity of the situation as a critical event.
that's no laughing matter
Indicates that the situation is not humorous and demands respect.
that's a dangerous game
Implies risky actions with potentially severe negative consequences.
that's playing with fire
Highlights recklessness and potential harm in the described actions.
FAQs
How can I use "that's serious" in a sentence?
You can use "that's serious" to express the importance or severity of a situation. For example, "When I heard about the accident, I thought, "that's serious, we need to act immediately.""
What are some alternatives to "that's serious"?
You can use alternatives like "that's a grave matter", "that's concerning", or "that's significant" depending on the context.
Is "that's serious" suitable for formal writing?
While generally acceptable, "that's serious" is more suited for informal or neutral contexts. In formal writing, consider using phrases like "that is a grave matter" or "that is a significant concern".
What makes a situation qualify as "that's serious"?
A situation described as "that's serious" typically involves potential negative consequences, urgency, or significant impact on individuals or communities.
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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
85%
Authority and reliability
4.5/5
Expert rating
Real-world application tested