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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
main line of work
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "main line of work" is correct and can be used in written English.
You can use this phrase when referring to the profession or job that a person usually does or specializes in. For example: "He has been a teacher for 20 years, so teaching is his main line of work."
✓ Grammatically correct
News & Media
Science
Formal & Business
Alternative expressions(16)
primary occupation
chief vocation
core business activity
area of expertise
primary line of business
central operation
principal business sector
chief commercial activity
major line of business
primary revenue stream
principal line of business
basic line of business
essential function
core competency
main place of work
main line of business
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
8 human-written examples
But that's because it's not his main line of work.
News & Media
At that time his main line of work was the study of the properties of the α-particle, already begun in Montreal and continued with increased vigour in Manchester.
Science & Research
Speaking of reaching out, it has been three years since Ron Kochel and Gene Gulich of Passaic caused a stir at the Abilities Expo in Edison with their adaptive pinball machine, something they had developed almost as an afterthought (their main line of work being a glass-replacement business).
News & Media
His follow-up essay begins with a reference to Graham's complaint, which he links to a larger trend: In my main line of work as a film critic, I have watched over the past 15 years as the studios committed their vast financial and imaginative resources to the cultivation of franchises (some of them based on those same Y.A. novels) that advance an essentially juvenile vision of the world.
News & Media
Mostly, the patent deals with ETAK's main line of work, which is installing wireless cell towers.
News & Media
–Press Secretary Robert Gibbs' main line of work has been as a flack for congressional and presidential campaigns; his government work is limited to a short run with a North Carolina House member and a preparatory stint in Obama's Senate office.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
52 human-written examples
The hundreds of attendees came from all over the Wiregrass, as the southeastern corner of Alabama is known, a quiet, rural region where the main lines of work are growing peanuts or building helicopters.
News & Media
The law detailed the health sector's responsibilities and supported earlier regional initiatives, to guide the main lines of work on IPV in the national health system.
Science
"Here the men stopped, and commenced firing; but a lull in the fire of the enemy enforced the order to move forward, and in little more time than it takes to write it we had captured and occupied a section of the main line of Confederate works," recounted a captain who later wrote a history of the regiment.
News & Media
The company's main line of business is to work for banks, matching their lists of depositors with Commerce Department lists of individuals whom banks are not supposed to transact business with because they are connected to terrorists, drug dealers or corrupt foreign officials.
News & Media
Unless things change dramatically in the next few months, the Republican candidate will make this his main line of attack, and it might well work.
News & Media
Expert writing Tips
Best practice
When describing someone's profession, use "main line of work" to clearly indicate their primary occupation, especially when they have multiple roles or side projects.
Common error
Avoid using "main line of work" to describe hobbies or occasional jobs. This phrase should represent the person's primary professional focus.
Source & Trust
86%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "main line of work" functions as a noun phrase, typically serving as a subject complement or object in a sentence. It identifies an individual's principal occupation or professional focus, as supported by examples in Ludwig.
Frequent in
News & Media
43%
Science
29%
Formal & Business
14%
Less common in
Wiki
14%
Encyclopedias
0%
Academia
0%
Ludwig's WRAP-UP
In summary, "main line of work" is a grammatically correct and generally neutral phrase used to describe someone's primary profession or occupation. While Ludwig identifies it as a valid and understandable expression, it's important to use it accurately, distinguishing it from secondary activities or hobbies. Alternatives like "primary occupation" or "principal profession" can be used for variety. As Ludwig examples show, this phrase appears most frequently in News & Media, Science, and Formal & Business contexts, indicating its broad applicability in professional and informative communications.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
primary occupation
Focuses on the principal activity for which one is employed.
principal profession
Highlights the major professional field in which someone works.
chief vocation
Emphasizes the main calling or career.
main source of income
Focuses on the primary means by which one earns money.
core business activity
Specifically applies to a business's primary revenue-generating activity.
career focus
Emphasizes the central theme or direction of one's professional life.
area of expertise
Highlights the specific skills and knowledge one possesses professionally.
professional specialty
Indicates a specific area of specialization within a profession.
day job
An informal term for one's regular, primary employment.
bread and butter
An idiomatic expression for one's main source of livelihood.
FAQs
How can I use "main line of work" in a sentence?
You can use "main line of work" to describe someone's primary profession, as in "His "main line of work" is software engineering, but he also enjoys freelance photography".
What is a good substitute for the phrase "main line of work"?
Consider using alternatives like "primary occupation", "principal profession", or "chief vocation" depending on the specific context.
Is it appropriate to use "main line of work" in formal writing?
Yes, "main line of work" is suitable for formal writing. It clearly and professionally conveys the idea of someone's primary profession.
What's the difference between "main line of work" and "side hustle"?
"Main line of work" refers to your primary job or profession, while "side hustle" describes a secondary job or business undertaken for additional income or passion.
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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
86%
Authority and reliability
4.5/5
Expert rating
Real-world application tested