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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
indicates how long
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "indicates how long" is correct and usable in written English.
You can use it when discussing duration or time-related information in various contexts, such as research, reports, or everyday conversation. Example: "The study indicates how long the treatment should last for optimal results."
✓ Grammatically correct
News & Media
Science
Formal & Business
Alternative expressions(2)
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
15 human-written examples
The Serpentine Gallery denies that the work's title, 512 Hours, indicates how long you will have to queue for.
News & Media
It also indicates how long it would take to complete the trip both with Kutsuplus and with other modes of transport.
News & Media
It indicates how long a battery has left until it runs out and also offers alerts about whether power-hungry systems like GPS are turned on.
News & Media
A time rating, ranging from 30 minutes to four hours, indicates how long the inside of the safe can maintain the designated temperature while the exterior is engulfed in flames.
News & Media
At the top of the page, there's a countdown that indicates how long the deals will be available.
News & Media
On the occurrence of any starvation instant, SL indicates how long (in frames) this starvation will last.
Human-verified similar examples from authoritative sources
Similar Expressions
45 human-written examples
Neither Mr. Lee nor Mr. Bush indicated how long they would be willing to give North Korea to make its declaration.
News & Media
The ZD people have not indicated how long they plan to keep topping the Abacus solera with fresh cabernet.
News & Media
SHOULD beauty products be stamped with expiration dates like cartons of milk, indicating how long they will last before turning?
News & Media
Thus, the types of insects or eggs present in a corpse indicate how long the victim has been dead.
Encyclopedias
The board did not indicate how long this policy would continue, a decision that Mr. Bernanke described as intentional.
News & Media
Expert writing Tips
Best practice
When using "indicates how long", ensure that the unit of time is clear from the context. For example, "The timer indicates how long the process will take in minutes."
Common error
Avoid using "indicates how long" without specifying what exactly is being measured. For instance, instead of saying "The graph indicates how long," specify "The graph indicates how long the reaction took to complete."
Source & Trust
85%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "indicates how long" functions as a verb phrase that introduces a dependent clause specifying a duration or length of time. As Ludwig AI confirms, this phrase is correct and usable in written English.
Frequent in
News & Media
44%
Science
38%
Formal & Business
6%
Less common in
Encyclopedias
2%
Reference
0%
Social Media
0%
Ludwig's WRAP-UP
The phrase "indicates how long" serves to specify a duration or length of time, and is considered grammatically correct by Ludwig. As the analysis reveals, it's frequently employed in news and media, as well as scientific and formal business contexts. For alternative phrasing, consider options like "shows the duration" or "specifies the length". When using "indicates how long", ensure clarity by explicitly stating what's being measured and including the relevant unit of time. Remember, Ludwig confirms that the phrase is correct, making it a reliable choice for your writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
shows the duration
Replaces "indicates" with a more direct synonym and simplifies the structure.
specifies the length
Uses "specifies" for greater precision and focuses on "length" as the key aspect.
reveals the time frame
Substitutes "reveals" for "indicates" and uses "time frame" to denote the duration.
denotes the period
Employs "denotes" for a more formal tone and "period" to represent the duration.
outlines the time span
Replaces "indicates" with "outlines" and uses "time span" to signify the duration.
details the duration
Uses "details" for emphasis and focuses on the "duration".
clarifies the time period
Substitutes "clarifies" for "indicates" for better understanding and uses "time period" to refer to the duration.
designates the length of time
Employs "designates" for a formal context and spells out "length of time" for clarity.
represents the duration
Uses "represents" as a synonym for "indicates", keeping the key term "duration".
defines the interval
Replaces "indicates" with "defines" and employs "interval" as a technical term for duration.
FAQs
How can I rephrase "indicates how long" for variety?
You can use alternatives such as "shows the duration", "specifies the length", or "reveals the time frame" depending on the context. These options provide similar meaning while varying your word choice.
Is "indicates how long" formal or informal?
The phrase "indicates how long" is generally neutral and can be used in both formal and informal contexts. However, for more formal writing, consider using alternatives like "designates the length of time".
What's the difference between "shows the duration" and "indicates how long"?
"shows the duration" is a more direct and simplified way of expressing the same concept as "indicates how long". The latter is slightly more formal.
How to use "indicates how long" in a sentence?
You can use "indicates how long" to describe something that reveals a duration. For example, "The manual indicates how long the battery lasts on a single charge."
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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