“Since ancient times, education has played a vital role in the development of every nation.” This opening, or a variation of it, appears in countless manuscripts. An editor reads it and knows two things at once: the author was not sure where to begin, and at least another page must be read before the paper reveals what it is about.
The Introduction to a research article has a narrow task: move readers from what is known to your precise question, and convince them the question is worth answering. A three-move model widely taught in academic writing courses, known as CARS (Create a Research Space), helps do this efficiently.
The three moves
| Move | Purpose | Sentence frames |
|---|---|---|
| 1. Establish the territory | Show the topic matters and summarise what is known | “A growing body of research has examined…”; “There is consistent evidence that…” |
| 2. Establish a niche | Show what is missing, contradictory or unasked | “However, most of this work has focused on…”; “What remains unclear is…” |
| 3. Occupy the niche | Present how your study fills that niche | “This study examines…”; “We make two contributions…” |
The three moves match three questions readers silently ask: does this topic matter, what is still unknown, and what does this paper do about it?
Move 1: start more specifically than you think
Your first sentence should be specific enough that it could only open this paper or a small family of papers on the same topic. Compare:
- Generic: “Education plays an important role in modern society.”
- Specific: “In many school systems, a large share of new teachers consider leaving within their first few years, and that period largely determines whether they stay.”
The second sentence places the reader inside the problem immediately. If you use a figure in such a sentence, cite a reliable source; if you lack solid data for your context, describe the problem in words rather than guessing a number.
Move 1 usually spans one or two paragraphs: state the problem, then summarise what research has established, with grouped citations. There is no need to recount individual studies; that belongs in a literature review section if you have one.
Move 2: a gap needs a reason
This is the decisive move. Common ways to establish a niche:
- Counter-claim: “However, recent studies report conflicting results…”
- Indicating a gap: “Most evidence comes from cross-sectional surveys, leaving the direction of effects unclear.”
- Raising a question: “Whether this mechanism holds in rural schools has not been examined.”
- Extending: “Framework X has not been applied to group Y, although there are reasons to expect…”
The weakest niche is “no study has examined this topic in country Z” without explaining why country Z might produce different results. Reviewers will ask: so what? If the mechanism is identical elsewhere, what does one more replication add? Name the specific features of your context — system structure, recruitment practices, organisational culture — that make the question worth asking again.
Move 3: say plainly what the paper does
The final paragraph of the Introduction usually contains:
- The aim or research question, stated clearly, not buried in a long sentence.
- The approach in one sentence: design and data.
- The contribution: one to three specific points.
- Depending on the field, a roadmap of the paper in one sentence (common in economics and engineering, rare in biomedicine).
Some fields also preview the main findings in the Introduction. Economics and computer science often do; biomedicine rarely does. Check recent articles in your target journal and follow their convention.
A four-paragraph Introduction skeleton
Paragraph 1 (territory): Early-career teacher attrition is a problem in many systems; colleague support has repeatedly been identified as an important retention factor.
Paragraph 2 (territory, continued): The proposed mechanism is that colleague support reduces isolation and builds professional self-efficacy.
Paragraph 3 (niche): Evidence comes mainly from large urban schools with several colleagues per subject. In small remote schools a teacher may be the only one teaching their subject, so support must come from elsewhere, and it is unclear whether the mechanism holds.
Paragraph 4 (occupying): This study uses two-year panel data on new teachers in remote schools to test whether cross-school support networks play a role comparable to within-school support. Contributions: extending theory to low-colleague settings; informing the design of cross-school mentoring.
Length and common mistakes
For a 6,000–8,000-word article, the Introduction typically runs to 600–1,000 words across four to six paragraphs. Frequent problems:
- Opening with a universal claim or distant history.
- An overlong Move 1 and a one-sentence Move 2.
- No sentence stating the aim, leaving readers to infer it.
- Promising contributions the Discussion never delivers.
- Author-by-author citation instead of synthesis.
Check the fit with your Discussion
Place the last paragraph of your Introduction beside the first paragraph of your Discussion. The question posed in one must be answered in the other; the contributions promised in one must be discussed in the other. If they do not match, revise the Introduction — it is usually easier than rewriting the Discussion.
Next step: label each paragraph of your current Introduction as Move 1, 2 or 3 in the margin. If Move 2 occupies a single sentence, write a full paragraph explaining why the gap matters before you touch anything else.
Câu hỏi thường gặp
What is the CARS model for writing introductions?
CARS (Create a Research Space) is a three-move model: establish the territory, identify a niche or gap, and present your study as filling it. It is widely used in academic writing teaching.
How long should the introduction of a research paper be?
For a 6,000–8,000-word article, around 600–1,000 words across four to six paragraphs is typical. Check recent articles in your target journal.
How should I start the introduction of a research paper?
Open with a sentence specific to your topic and problem. Generic statements such as “education is important” lose the editor’s attention from the first line.
Is “no research has been done in my country” a valid research gap?
Not on its own. Explain why your country’s context might lead to different results, naming specific features that make the question worth revisiting.
Should I state my main findings in the introduction?
It depends on the field. Economics and computer science often preview findings, while biomedicine rarely does. Follow the convention of your target journal.
