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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
letter in which
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "letter in which" is correct and usable in written English.
It can be used to refer to the content or context of a specific letter, often when explaining or describing its contents. Example: "In the letter in which I addressed the concerns, I also proposed several solutions."
✓ Grammatically correct
News & Media
Science
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
60 human-written examples
Within hours came a second anonymous letter, in which the writer, later revealed as Maj.
News & Media
Shahrudi issued a public letter in which he denounced the bloggers' treatment in prison.
News & Media
This was the first letter in which he forgot to ask us how we were.
News & Media
"It is a nightmare," began his letter in which he apologetically rejected the story.
News & Media
I enclose [censored] letter, in which you may wish to read the two underlined sentences.
News & Media
Write your own letter in which you express your reaction to the series.
News & Media
His column includes that letter, in which he gives arguments on behalf of Ms. Day.
News & Media
Sinclair Lewis has written letter in which he has won over to artists side some Rotarians.
News & Media
Campbell cites a published letter in which Kerouac stated, "I have no proficiency at all in my native language".
News & Media
Mrs. Cork shows her a letter in which the writer, Rosie, asks her husband for a necklace and his flute.
News & Media
Quotes from a letter in which his uncle discusses being "saved" from a relationship that was heading for marriage.
News & Media
Expert writing Tips
Best practice
Use "letter in which" to clearly connect a letter to its specific content or purpose, enhancing clarity and avoiding ambiguity. For example: 'The letter in which he resigned detailed his reasons for leaving.'
Common error
Avoid replacing "in which" with "that" when describing the content of a letter. While "that" can sometimes work, "in which" often provides a more precise and formal connection. For example, prefer 'the letter in which she explained her decision' over 'the letter that she explained her decision'.
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "letter in which" functions as a prepositional phrase that modifies a noun (letter), indicating the letter's content or specific purpose. As Ludwig AI points out, it is grammatically correct and widely used across varied sources.
Frequent in
News & Media
41%
Science
38%
Formal & Business
7%
Less common in
Wiki
5%
Academia
3%
Encyclopedias
0%
Ludwig's WRAP-UP
In summary, the phrase "letter in which" is a grammatically sound and frequently used prepositional phrase. Ludwig AI confirms it is correct and widely accepted. It serves to provide specific context or details about the contents or purpose of a letter. While suitable for both formal and informal settings, it is most commonly found in News & Media and Scientific contexts. When using this phrase, ensure that it clearly connects the letter to its content to avoid any ambiguity, and consider that alternatives such as "letter containing" might be a better fit depending on the context.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
letter containing
Focuses on the letter's content, specifying what it includes.
letter that details
Emphasizes the specific information provided within the letter.
letter wherein
A more formal and somewhat archaic alternative.
letter that specifies
Highlights the letter's role in setting out particular conditions or information.
letter describing
Focuses on the descriptive nature of the letter's content.
letter outlining
Highlights the letter's structured presentation of information.
letter discussing
Focuses on the subject matter being addressed in the letter.
letter addressing
Highlights the letter's engagement with a particular issue.
letter in which is stated
Adds emphasis to a declaration made inside the message.
letter with details of
Emphasizes the inclusion of specific information within the letter.
FAQs
How can I use "letter in which" in a sentence?
Use "letter in which" to specify the content or context of a particular letter. For example, "I received a "letter in which" they outlined their proposal."
What are some alternatives to "letter in which"?
Alternatives include "letter containing", "letter that details", or "letter addressing", depending on the specific nuance you want to convey.
Is it correct to say "letter that" instead of "letter in which"?
While "letter that" is sometimes grammatically acceptable, ""letter in which"" is generally more precise and formal, especially when referring to the contents of the letter.
What's the difference between "letter in which" and "letter about"?
"Letter in which" specifically refers to the content included within the letter, whereas "letter about" refers to the general topic or subject that letter concerns. Example: 'I wrote a letter about my concerns' versus 'I wrote a "letter in which" I detailed my concerns'.
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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