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Ludwig provides contextual example sentences from reliable sources like The New York Times, BBC, and academic publications, helping you understand how words and phrases are used in real-world contexts. This improves both writing fluency and comprehension skills.

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Ludwig focuses on providing real example sentences from authoritative sources, not just grammar checking. This contextual approach helps users understand not just what's correct, but how language is actually used by native speakers and professional writers.

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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.

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CEO of Professional Science Editing for Scientists @ prosciediting.com

Certain period of time
Grammar usage guide and real-world examples

USAGE SUMMARY

The phrase "certain period of time" is correct and frequently used in written English
You can use it to refer to an amount of time that is not specified. For example, "I will be unavailable for a certain period of time as I am working on a project."

✓ Grammatically correct

News & Media

Science

Academia

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

It just defers it for a certain period of time.

News & Media

The New York Times

DEFINITION: distance traveled over a certain period of time.

Academia

Harvard University

"It helps for a certain period of time," Ghaith said.

News & Media

The Washington Post

You can only be useful at a job like this for a certain period of time.

News & Media

The New Yorker

One focused on increasing registrations to a product over a certain period of time.

News & Media

The Guardian

Whether actualized or not, these possibilities continue during a certain period of time.

Encyclopedias

Britannica

After a certain period of time, these records are generally not needed for those reasons.

Academia

Cornell University

Speed is defined as a distance traveled over a certain period of time.

Academia

Harvard University

You typically need to use the card at the retailer within a certain period of time.

News & Media

The New York Times

Fixed rates Fixed-rate ISAs mean tying up your money for a certain period of time.

News & Media

Independent

After a certain period of time the bed temperature profile evens out.

Science

Journal of the Taiwan Institute of Chemical Engineers

Expert writing Tips

✓ Best practice

When using "certain period of time", clarify the context to prevent ambiguity. For example, specify whether it's days, weeks, months, or years if precision is needed.

⚠ Common error

Avoid using "certain period of time" without any contextual clues. If possible, provide an approximate duration (e.g., 'within a few weeks') to give your audience a better understanding.

Antonio Rotolo, PhD

Digital Humanist | Computational Linguist | CEO @Ludwig.guru

Linguistic Context

The phrase "certain period of time" functions as an adverbial phrase, modifying a verb by specifying when an action occurs or a condition exists. It indicates an unspecified duration. Ludwig confirms its correct and frequent use.

Expression frequency: Very common

✓ Frequent in

News & Media

36%

Science

32%

Academia

10%

⚠ Less common in

Wiki

Encyclopedias

Formal & Business

Ludwig's WRAP-UP

In summary, "certain period of time" is a grammatically correct and frequently used phrase to denote an unspecified duration. As Ludwig AI confirms, it is appropriate for various contexts, including News & Media, Science, and Academia. While versatile, clarifying the context or providing approximate durations when possible improves clarity. Consider alternatives such as "specific duration" or "defined timeframe" for added precision. Be mindful of overly vague usage to prevent confusion.

Alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

specific duration

Replaces 'period' with 'duration' and 'certain' with 'specific', maintaining the meaning with slightly more formal vocabulary.

defined timeframe

Emphasizes the setting of boundaries for the time interval, implying a pre-determined limit.

specified time interval

Replaces 'period' with 'interval', making the phrase more precise and technical.

particular duration

Substitutes 'certain' with 'particular', suggesting a specific rather than vague duration.

designated time

Implies that the duration has been officially or formally assigned.

allotted time

Suggests that the duration has been portioned out or allocated for a specific purpose.

More alternative expressions(6)

safe period of time

undetermined period of time

definite period of time

fixed period of time

various period of time

little period of time

FAQs

How can I use "certain period of time" in a sentence?

You can use "certain period of time" to refer to a duration that isn't precisely defined, as in, "The effects will be visible after a "certain period of time"".

What are some alternatives to using "certain period of time"?

Depending on the context, you might use alternatives such as "specific duration", "defined timeframe", or "specified time interval".

Is it better to specify the duration instead of saying "certain period of time"?

Specifying the duration, like "two weeks" or "three months", is preferable for clarity. Use "certain period of time" when the exact duration is unknown or unimportant.

What's the difference between "certain period of time" and "specific period of time"?

"Specific period of time" implies a more defined or measurable duration, while "certain period of time" is vaguer and less precise.

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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

81%

Authority and reliability

4.5/5

Expert rating

Real-world application tested

Most frequent sentences:

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Certain period of timeGrammar usage guide and real-world examples

Certain period of time
Grammar usage guide and real-world examples