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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
filling in for
Grammar usage guide and real-world examplesUSAGE SUMMARY
"filling in for" is a correct and usable phrase in written English.
You can use it when you are substituting for someone or something else. Example sentence: I am temporarily filling in for the receptionist while she is on vacation.
✓ Grammatically correct
News & Media
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
"I'm filling in for him.
News & Media
(Mr. Kulik was filling in for Mr. Taylor).
News & Media
Milledge has been filling in for Beltrán.
News & Media
Secretaries, janitors and teachers are filling in for absent officers.
News & Media
He was filling in for Ahman Green then.
News & Media
Nadiya Takolia here, filling in for Riazat this week.
News & Media
He was filling in for the injured JaMarcus Russell.
News & Media
Parul Sehgal is the host, filling in for Pamela Paul.
News & Media
Yandle is filling in for Atlanta Thrashers defenseman Tobias Enstrom.
News & Media
Michael Early has been filling in for Brown, while Kris Farris has spent the last few days filling in for Jennings.
News & Media
Jordan Todman and Fitzgerald Toussaint combined for 123 yards rushing filling in for DeAngelo Williams.
News & Media
Expert writing Tips
Best practice
When using "filling in for", ensure the context makes it clear who or what is being replaced and the duration of the substitution, if relevant.
Common error
Avoid assuming complete authority when "filling in for" someone unless explicitly stated. Clarify the scope of your responsibilities to prevent overstepping or neglecting important tasks.
Source & Trust
87%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "filling in for" functions as a prepositional verb indicating temporary substitution or replacement. Ludwig examples show it is commonly used to describe someone taking over another's duties or role for a limited period.
Frequent in
News & Media
92%
Formal & Business
4%
Science
2%
Less common in
Encyclopedias
1%
Wiki
0.5%
Reference
0.5%
Ludwig's WRAP-UP
In summary, "filling in for" is a very common and grammatically sound phrase used to indicate temporary substitution. As confirmed by Ludwig, it finds its primary use in contexts such as News & Media. When using this phrase, ensure clarity regarding the scope and duration of the temporary replacement. Be mindful to avoid making assumptions about full authority unless explicitly granted. Alternatives such as ""substituting for"" or ""covering for"" can be employed depending on the specific nuance you want to convey.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
substituting for
Indicates a direct replacement of one thing for another, emphasizing the act of substitution.
standing in for
Suggests a temporary replacement, often in a formal or official capacity.
covering for
Implies taking on someone's responsibilities during their absence.
acting as a substitute for
A more formal way of expressing the act of replacing someone or something.
taking the place of
Focuses on the position or role being occupied by the replacement.
temporarily replacing
Highlights the temporary nature of the substitution.
stepping in for
Suggests a quick and often unplanned replacement.
Pinch-hitting for
An idiomatic expression mainly used in sports context or in the business environment to express a sudden replacement.
understudying
Specifically refers to learning a role in order to be able to replace the main actor, mostly used in theaters.
holding the fort
Idiomatic way to express that you are guarding or keeping things steady in somebody's absence.
FAQs
How can I use "filling in for" in a sentence?
You can use "filling in for" to indicate that someone is temporarily replacing another person or thing. For example, "I'm "filling in for" the manager while she's on vacation".
What are some alternatives to "filling in for"?
Alternatives include "substituting for", "standing in for", or "covering for", depending on the specific context.
Is it correct to say "fill in for" instead of "filling in for"?
Yes, "fill in for" is the infinitive form, while "filling in for" is the present participle. Both are correct, but used in different grammatical constructions. For example, "I need someone to fill in for John", vs. "I am filling in for John".
What's the difference between "filling in for" and "replacing"?
"Filling in for" implies a temporary substitution, while "replacing" suggests a permanent change. "Replacing" indicates that someone or something is permanently taking the place of another.
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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
87%
Authority and reliability
4.6/5
Expert rating
Real-world application tested