Writing Science

To the dismay of many science students, the field of science is not exempt from conventions of good writing; composing clear and effective prose is an essential skill for all students, regardless of discipline. Although this skill takes time to develop, there are several basic guidelines that will help improve your writing.

Your lab report must be written with complete paragraphs and sentences. Thus, bullet points or other incomplete sentence structures are never appropriate. It is also important that your writing be clear, concise, and direct. This means that you should use the active voice whenever possible; use appropriate and consistent tense; avoid unnecessary words, phrases, and jargon; use modifiers judiciously; and put the main verb early in the sentence and keep it close to its subject.

• Paragraphs and Sentences
• Voice: Active vs. Passive
• Verb Tense
• Unnecessary Words and Jargon
• Precision and Accuracy

Paragraphs and Sentences

Paragraphs are the building blocks of all writing assignments.

Two important features of paragraphs are that (1) they have a single controlling idea and that (2) the controlling idea is supported with relevant details, examples, and analysis. The controlling idea must be summarized in the first sentence, which is often referred to as the topic sentence, and all ideas throughout the paragraph must connect to it. The final sentence should provide a link between the controlling idea and the purpose of the lab report. The first and/or last sentences should also transition between the previous and next paragraphs, respectively. Effective paragraphs are 100 to 200 words in length – too short, and detail is often missing; too long, and more than one controlling idea is often present.

Paragraph checklist

• Contains a single controlling idea
• Begins with a topic sentence that summarizes the controlling idea
• Uses details, examples, and analysis to support and develop the idea
• Is no longer than one printed page (between 100 and 200 words)

Read more about effective paragraphs and transitions.

Sentences

Sentences are the basic unit of writing. Although seemingly simple, sentences pose many troublesome problems for writers. It is important to understand a few of the most common errors:

• Sentence fragments
• Run-on sentences and comma splices
• Faulty parallelism
• Subject-verb agreement
• Pronoun reference and agreement

A good way to spot errors in sentences, even if you aren’t familiar the terminology, is to read your writing aloud, slowly and carefully. This will highlight awkward structures that you can then rework to correct. Learn about more proofreading strategies in the Writing Science guide.

Voice: Active vs. Passive

You may have received comments on past assignments that say “use active voice”, but you may not know what that actually means. The active and passive voices are different sentence constructions. The passive voice is not grammatically incorrect, but it can be awkward, unclear, and indirect. Therefore, use the active voice when possible to produce clear and direct writing.

Passive Voice

Construction: Object - Verb - Subject
Focus: Objective – the object is the focus of the sentence
Result: Obscures who/what is doing the action
Attributes: Indirect and cumbersome
Examples:  “The plants were measured by group members…” 

“It has been found that…”

Active Voice

Construction: Subject - Verb - Object
Focus: Subjective – the subject is the focus of the sentence
Result: Highlights who/want is doing the action
Attributes: Direct and clear
Examples: “Group members measured the plants…” (shorter than passive voice example)
“Smith et al. (2013) found XYZ…” (who discovered XYZ is relevant)

Read more about active and passive voice

Verb Tense

Maintaining a consistent and appropriate tense in your writing is important for clarity and accuracy. As noted in the discussion of lab report sections, use the following tenses where appropriate. 

Past Tense

Use it in all sections when:

• Referring to events that occurred in the past
• Referring to what you did
• Referring to results obtained in the past (in your study and others’ studies)

Examples

• “Smith et al. (2013) found that” 
• “We hypothesized that”
• “My group measured the”
• “The results supported my hypothesis that”

Present Tense

Use it in the Introduction and Discussion only when:

• Referring to implications of your results
• Presenting established knowledge

Examples

• “These results indicate that”
• “Frogs are amphibians”

Future Tense

Use it in the Discussion only when:

• Suggesting what you will study in the future

Example

• "Future studies should investigate…"

Unnecessary Words & Jargon

Jargon is specialized terminology used by a group/field/profession that is difficult for others to understand; use it sparingly. If you must use a specialized term, be sure to define it clearly upon first use.

Extra words can make writing awkward and cumbersome. Simpler is generally better, so long as neither clarity nor accuracy is affected. When reviewing your work, look for wordiness and reduce instances to simpler, more direct language. The following list includes many common examples:

• Replace "due to the fact that" with "because"
• Replace "has an effect on" with "affects"
• Replace "utilize/utilization" with "use"
• Replace "a majority of" with "most"
• Replace "a number of" with "many"
• Replace "are of the same opinion" with "agree"
• Replace "less frequently occurring" with "rare"
• Replace "all three of the" with "the three"
• Replace "give rise to" with "cause"
• Replace "in order to" with "to"

Be Precise and Accurate

It is important that the reader understand exactly what you mean to say; therefore, be as specific and accurate in your terminology and avoid colloquial words and phrases.

Be specific, not general

Instead of "a period of time" write "a week (or a month, a day, an hour)"
Instead of "bad weather" write "heavy rain and 40 km/hr winds"

Be concrete, not abstract

Instead of "forest" write "mature stand of mixed deciduous"
Instead of "responded well" write "increased"

Be formal, not colloquial

Instead of "nowhere near" write "far from"
Instead of "lots of or a lot" write "most or many"