How to Write a Paragraph for Your Scientific Paper

This blog post has all you need to know about writing scientific paragraphs: You’ll learn the optimal research paper paragraph structure, how long a paragraph in a scientific paper should be, and how to write a good topic sentence (yes, I’ll show you some good scientific paragraph examples).

Publishing a well-written scientific research paper goes beyond being proficient in English. What’s more important is being able to write clear and well-structured scientific papers — especially if you want to get published in high-impact journals and get cited consistently.

One of the most important structural units of a scientific paper is the paragraph. Yet, most researchers don’t know how to write science paragraphs to create a well-structured scientific paper that every reader would find a pleasure to read.

In this blog post, I’ll answer the following questions about writing science paragraphs:

How long should a paragraph be in a research paper?
What is the topic sentence and what is the concluding sentence in a science paragraph?
What is the best research paper paragraph structure?

Okay, let’s go:

The most common problem with scientific paragraphs I see is that they are too long. Often this is because authors are covering more than one topic per paragraph (see section “What is the best research paper paragraph structure?” below). The problem with long science paragraphs is that they are hard to read, especially if the author meanders through several different topics without the main message of the scientific paragraph being clear.

Don’t be afraid of short and concise paragraphs! A length of 100-200 words for a science paragraph is optimal. If your paragraphs tend to be longer, I suggest analysing them to see how you could divide them up sensibly.

WHAT IS THE TOPIC SENTENCE AND WHAT IS THE CONCLUDING SENTENCE IN A SCIENCE PARAGRAPH?

The first and last sentences, called topic and concluding sentences, respectively, are the strongest positions of a science paragraph. Even when people only skim-read your scientific paper, they tend to pay a more attention at the beginning and the end of structural units such as sections, subsections, and paragraphs. In fact, I often catch myself only reading the first sentence of a paragraph to decide whether it’s worth reading the whole paragraph or whether I want to skip to the next one. Therefore, it is wise to make use of the first and last positions in science paragraphs. Let me show you how below.

EXAMPLES OF TOPIC SENTENCES IN SCIENCE PARAGRAPHS

In the first sentence, it is crucial to signal to the reader what the paragraph will be about. One way to do this is to provide a topic sentence, which summarises the content of the paragraph.

Here is a scientific paragraph example of a well-crafted topic sentence:

There are a number of clear advantages in extending the spectral range of SPAD detectors into the short-wave infrared region […].” Firstly, compatibility with the optical fibre low-loss telecommunications windows is a fundamental advantage in many fibre-based applications. Secondly, [….] Thirdly, […] Finally, operation in the SWIR will mean enhanced atmospheric transmission, especially through obscurants such as smoke, smog, fog and haze.
Vines et al., Nature Communications 10, 1086 (2019).

Here, the first sentence (“There are a number of clear advantages in extending the spectral range of SPAS detectors into the short-wave infrared region”), the topic sentence, states that there are many advantages for modifying the model system. The paragraphs then continues listing these advantages (“firstly, …”, “secondly,…”, “thirdly,…”, “finally,…”).

In science paragraph writing, it’s often advisable to present the conclusion at the beginning of the paragraph, in the topic sentence, instead of in the concluding sentence. This prepares the reader for what is to follow without them having to keep a lot of information in their head before being presented with the conclusion. This means your writing will be clearer to them and it will be less effort to read your scientific paragraphs — always a good thing!

Here’s another scientific paragraph example that demonstrates stating the conclusion in the topic sentence:

The measured DCR demonstrates a vast improvement when compared to previous Ge-on-Si work. Warburton et al. reported […] There is a similar relationship when our results are compared to results from Martinez et al., who reported […] This considerable reduction in DCR has resulted from […] In order to fully ascertain the relative contributions to DCR, we are initiating a series of measurements on samples with different diameters and Ge thicknesses.
Vines et al., Nature Communications 10, 1086 (2019).

Here, the topic sentence (“The measured DCR demonstrates a vast improvement when compared to previous Ge-on-Si work”) presents the main conclusion. In the following sentences, the authors go into detail about the evidence supporting this conclusion and offer interpretations. The last sentence (“In order to fully ascertain the relative contributions to DCR, we are initiating a series of measurement on samples with different diameters and Ge thicknesses”) — technically the concluding sentence — describes the next step, an outlook of future experiments to be performed.

Image advertising free academic writing class for researchers who like this blog post on writing science paragraphs

Using both topic and concluding sentences when writing science paragraphs

In some parts of your paper it will make sense to use both a topic and a concluding sentence in your scientific paragraph. For example, you might describe the idea or purpose behind an experiment in the topic sentence. The science paragraph would continue to outline the methodology and results of the experiment. The concluding sentence would then present the conclusion or interpretation of the results of the experiment.

Here is an example of using both topic and concluding sentences in science paragraph writing:

The subjects learned stimulus-outcome relationships that required the formation of conjunctive representations. Our task was based on […] The task stimuli consisted of […] We used […]. AB and C predicted the target 70% of the time and B and AC predicted the target 30% of the time. […] Optimal performance required learning the value of stimuli as distinct conjunctions of features (i.e., conjunctive representations).
Ballard et al., Nature Communications 10, 1073 (2019).

Here, the topic sentence (“The subjects learned stimulus-outcome relationships that required the formation of conjunctive representations”) describes what the experiment is about. A quick note from me: I think this topic sentence could be slightly improved by adding what the purpose of the experiment was. The science paragraph continues to give more details on the approach, methodology and results of the experiment. And, as suggested above, the concluding sentence in this scientific paragraph example (“Optimal performance required learning the value of stimuli as distinct conjunctions of features…”) communicates the conclusion of the performed experiment.

Let’s look at another science paragraph example of using both a topic and a concluding sentence:

To assess the possible impact on Bmp signalling, we analysed phospho-Smad159 (p-Smad159) localisation. […] Thus, higher levels of p-Smad159 cannot simply be explained due to increased expression of Bmp ligands.
Senft et al., Nature Communications 10, 1089 (2019).

Here, the authors clearly state the purpose and approach of their experiment in the topic sentence (“To assess the possible impact on Bmp signalling, we analysed phospho-Smad159 localisation.”). Accordingly, the concluding sentence communicates the take-home message of the performed experiment (“Thus, higher levels of p-Smad159 cannot simply be explained due to increased expression of Bmp ligands.”).

What is the best Research paper paragraph structure?

Communicate One main message per paragraph

I talk a lot about how important it is for a scientific paper to communicate a single main message. The same holds true for their building blocks – i.e., the science paragraphs. A paragraph should make sense on its own and communicate a clear message distinct from other paragraphs in your paper. If you are not able to summarise the content of a scientific paragraph you’ve written with a few keywords or in one simple sentence, the main message of your paragraph is unclear. This may be because you are covering two or more topics too different from each other in one paragraph, or because you need to add some information on how the topics are connected.

connect your paragraphs to create flow in the whole section of your scientific paper

Writing science paragraphs that communicate a single main message and have good topic and concluding sentences (see section “What is the topic sentence and what is the concluding sentence in a science paragraph?” above) isn’t enough. The paragraphs in your scientific paper also need to be connected with each other. Otherwise you’ve merely perfected completely distinct structural units. And that’s not what we want because in order to make your scientific paper easy to read, you need to create flow. Flow means that your reader will be able to go from one piece of information to the next one without ever getting stuck, wondering how things are connected.

On a paragraph level, you can achieve flow by relating back to information that was previously communicated in the topic sentence. Similarly, you can use the concluding sentence of a paragraph as a bridge to link to the topic sentence of the next paragraph.

Outline your paragraphs before you start writing your scientific paper

And one last tip: You’ll be writing your scientific paper more efficiently, if you plan out all paragraphs before you start typing out full sentences! Having a clear outline of your science paragraphs means that you only have to fill in the gaps. Dividing up a big task (e.g., “write an Introduction section”) into smaller tasks (e.g., “write one paragraph about topic X”) helps you overcome procrastination. You’ll still save time in the whole paper writing process even if you realise in the writing stage that you need to slightly adapt your outline. Finally, planning out your paragraphs beforehand will make it much easier to write a concise story that flows well.

Science paragraphs – 5 tips:

Okay, let’s recap my 5 top tips for writing scientific paragraphs:

The optimal length of a scientific paragraph is 100-200 words
Make good use of the strong positions of the topic and concluding sentences
Communicate one clear message in each science paragraph
Connect your paragraphs with each other to achieve a coherent paragraph structure in your research paper
Outline your science paragraphs before your start writing

Good luck with your science paragraph writing!

If you liked this blog post you’ll love our free training on how to get published in high-impact journals without lacking structure in the writing process. Click the orange button to watch now (or save for later)!

Image advertising free scientific writing class for researchers who like this blog post on writing science paragraphs

☝️ ☝️ ☝️

Share this article:

This blog post has all you need to know about writing scientific paragraphs: You’ll learn the optimal research paper paragraph structure, how long a paragraph in a scientific paper should be, and how to write a good topic sentence (yes, I’ll show you some good scientific paragraph examples).

Publishing a well-written scientific research paper goes beyond being proficient in English. What’s more important is being able to write clear and well-structured scientific papers — especially if you want to get published in high-impact journals and get cited consistently.

One of the most important structural units of a scientific paper is the paragraph. Yet, most researchers don’t know how to write science paragraphs to create a well-structured scientific paper that every reader would find a pleasure to read.

In this blog post, I’ll answer the following questions about writing science paragraphs:

How long should a paragraph be in a research paper?
What is the topic sentence and what is the concluding sentence in a science paragraph?
What is the best research paper paragraph structure?

Okay, let’s go:

The most common problem with scientific paragraphs I see is that they are too long. Often this is because authors are covering more than one topic per paragraph (see section “What is the best research paper paragraph structure?” below). The problem with long science paragraphs is that they are hard to read, especially if the author meanders through several different topics without the main message of the scientific paragraph being clear.

Don’t be afraid of short and concise paragraphs! A length of 100-200 words for a science paragraph is optimal. If your paragraphs tend to be longer, I suggest analysing them to see how you could divide them up sensibly.

WHAT IS THE TOPIC SENTENCE AND WHAT IS THE CONCLUDING SENTENCE IN A SCIENCE PARAGRAPH?

The first and last sentences, called topic and concluding sentences, respectively, are the strongest positions of a science paragraph. Even when people only skim-read your scientific paper, they tend to pay a more attention at the beginning and the end of structural units such as sections, subsections, and paragraphs. In fact, I often catch myself only reading the first sentence of a paragraph to decide whether it’s worth reading the whole paragraph or whether I want to skip to the next one. Therefore, it is wise to make use of the first and last positions in science paragraphs. Let me show you how below.

EXAMPLES OF TOPIC SENTENCES IN SCIENCE PARAGRAPHS

In the first sentence, it is crucial to signal to the reader what the paragraph will be about. One way to do this is to provide a topic sentence, which summarises the content of the paragraph.

Here is a scientific paragraph example of a well-crafted topic sentence:

There are a number of clear advantages in extending the spectral range of SPAD detectors into the short-wave infrared region […].” Firstly, compatibility with the optical fibre low-loss telecommunications windows is a fundamental advantage in many fibre-based applications. Secondly, [….] Thirdly, […] Finally, operation in the SWIR will mean enhanced atmospheric transmission, especially through obscurants such as smoke, smog, fog and haze.
Vines et al., Nature Communications 10, 1086 (2019).

Here, the first sentence (“There are a number of clear advantages in extending the spectral range of SPAS detectors into the short-wave infrared region”), the topic sentence, states that there are many advantages for modifying the model system. The paragraphs then continues listing these advantages (“firstly, …”, “secondly,…”, “thirdly,…”, “finally,…”).

In science paragraph writing, it’s often advisable to present the conclusion at the beginning of the paragraph, in the topic sentence, instead of in the concluding sentence. This prepares the reader for what is to follow without them having to keep a lot of information in their head before being presented with the conclusion. This means your writing will be clearer to them and it will be less effort to read your scientific paragraphs — always a good thing!

Here’s another scientific paragraph example that demonstrates stating the conclusion in the topic sentence:

The measured DCR demonstrates a vast improvement when compared to previous Ge-on-Si work. Warburton et al. reported […] There is a similar relationship when our results are compared to results from Martinez et al., who reported […] This considerable reduction in DCR has resulted from […] In order to fully ascertain the relative contributions to DCR, we are initiating a series of measurements on samples with different diameters and Ge thicknesses.
Vines et al., Nature Communications 10, 1086 (2019).

Here, the topic sentence (“The measured DCR demonstrates a vast improvement when compared to previous Ge-on-Si work”) presents the main conclusion. In the following sentences, the authors go into detail about the evidence supporting this conclusion and offer interpretations. The last sentence (“In order to fully ascertain the relative contributions to DCR, we are initiating a series of measurement on samples with different diameters and Ge thicknesses”) — technically the concluding sentence — describes the next step, an outlook of future experiments to be performed.

Using both topic and concluding sentences when writing science paragraphs

In some parts of your paper it will make sense to use both a topic and a concluding sentence in your scientific paragraph. For example, you might describe the idea or purpose behind an experiment in the topic sentence. The science paragraph would continue to outline the methodology and results of the experiment. The concluding sentence would then present the conclusion or interpretation of the results of the experiment.

Here is an example of using both topic and concluding sentences in science paragraph writing:

The subjects learned stimulus-outcome relationships that required the formation of conjunctive representations. Our task was based on […] The task stimuli consisted of […] We used […]. AB and C predicted the target 70% of the time and B and AC predicted the target 30% of the time. […] Optimal performance required learning the value of stimuli as distinct conjunctions of features (i.e., conjunctive representations).
Ballard et al., Nature Communications 10, 1073 (2019).

Here, the topic sentence (“The subjects learned stimulus-outcome relationships that required the formation of conjunctive representations”) describes what the experiment is about. A quick note from me: I think this topic sentence could be slightly improved by adding what the purpose of the experiment was. The science paragraph continues to give more details on the approach, methodology and results of the experiment. And, as suggested above, the concluding sentence in this scientific paragraph example (“Optimal performance required learning the value of stimuli as distinct conjunctions of features…”) communicates the conclusion of the performed experiment.

Let’s look at another science paragraph example of using both a topic and a concluding sentence:

To assess the possible impact on Bmp signalling, we analysed phospho-Smad159 (p-Smad159) localisation. […] Thus, higher levels of p-Smad159 cannot simply be explained due to increased expression of Bmp ligands.
Senft et al., Nature Communications 10, 1089 (2019).

Here, the authors clearly state the purpose and approach of their experiment in the topic sentence (“To assess the possible impact on Bmp signalling, we analysed phospho-Smad159 localisation.”). Accordingly, the concluding sentence communicates the take-home message of the performed experiment (“Thus, higher levels of p-Smad159 cannot simply be explained due to increased expression of Bmp ligands.”).

What is the best Research paper paragraph structure?

Communicate One main message per paragraph

I talk a lot about how important it is for a scientific paper to communicate a single main message. The same holds true for their building blocks – i.e., the science paragraphs. A paragraph should make sense on its own and communicate a clear message distinct from other paragraphs in your paper. If you are not able to summarise the content of a scientific paragraph you’ve written with a few keywords or in one simple sentence, the main message of your paragraph is unclear. This may be because you are covering two or more topics too different from each other in one paragraph, or because you need to add some information on how the topics are connected.

connect your paragraphs to create flow in the whole section of your scientific paper

Writing science paragraphs that communicate a single main message and have good topic and concluding sentences (see section “What is the topic sentence and what is the concluding sentence in a science paragraph?” above) isn’t enough. The paragraphs in your scientific paper also need to be connected with each other. Otherwise you’ve merely perfected completely distinct structural units. And that’s not what we want because in order to make your scientific paper easy to read, you need to create flow. Flow means that your reader will be able to go from one piece of information to the next one without ever getting stuck, wondering how things are connected.

On a paragraph level, you can achieve flow by relating back to information that was previously communicated in the topic sentence. Similarly, you can use the concluding sentence of a paragraph as a bridge to link to the topic sentence of the next paragraph.

Outline your paragraphs before you start writing your scientific paper

And one last tip: You’ll be writing your scientific paper more efficiently, if you plan out all paragraphs before you start typing out full sentences! Having a clear outline of your science paragraphs means that you only have to fill in the gaps. Dividing up a big task (e.g., “write an Introduction section”) into smaller tasks (e.g., “write one paragraph about topic X”) helps you overcome procrastination. You’ll still save time in the whole paper writing process even if you realise in the writing stage that you need to slightly adapt your outline. Finally, planning out your paragraphs beforehand will make it much easier to write a concise story that flows well.

Science paragraphs – 5 tips:

Okay, let’s recap my 5 top tips for writing scientific paragraphs:

The optimal length of a scientific paragraph is 100-200 words
Make good use of the strong positions of the topic and concluding sentences
Communicate one clear message in each science paragraph
Connect your paragraphs with each other to achieve a coherent paragraph structure in your research paper
Outline your science paragraphs before your start writing

Good luck with your science paragraph writing!

If you liked this blog post you’ll love our free training on how to get published in high-impact journals without lacking structure in the writing process. Click the orange button to watch now (or save for later)!

☝️ ☝️ ☝️

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Photography by Alice Dix