English Grammar Rules

For non-native English speakers, understanding and applying the various grammar rules of the English language can present a difficult challenge. Even for those that are familiar with English, this is further complicated by the nuances and conventions that are specific to scientific English. Our science editors come from a background of authorship, peer-review and journal editing, and are therefore confident in the scientific style.

At BIOEDIT, we want you to understand the changes we make to your work so that, while using our English grammar editing service, you can become better authors. To this end, we have provided below some common English grammar rules to aid you when writing your manuscript.

Punctuation

1. A semi-colon joins two complete sentences if the following are satisfied: the sentences are too closely related for a full stop, there is no connecting word requiring a comma, and the conditions for a colon are absent.
2. Use a colon after a clause that can stand alone and is followed by a list or explanation. It is not used after “was”, “were”, or “including”.
3. Use a colon to separate an independent clause from a quotation (A complete sentence: “quotation”.)
4. Use a hyphen to join two or more words serving as a single adjective before a noun (the well-known genotype), but not after a noun (the cells were well known).
5. Use a hyphen to join compound numbers (forty-two).
6. Use a hyphen with the prefixes “ex”, “self” and “all” (ex-husband); with the suffix “elect” (mayor-elect); and between a prefix and a capitalised word (anti-American).
7. Use a hyphen with figures (mid-1990s).
8. Use a hyphen to avoid confusion or an awkward combination of letters (semi-independent).
9. “I.e.,” (that is; in other words) and “e.g.,” (for example) are written with two periods and a comma.
10. Do not use the possessive apostrophe in acronyms (Incorrect: DNA’s).
11. Do not begin sentences with “and”.
12. Do not use a comma to join two independent clauses that are not joined by a coordinating conjunction (and, but, for, nor, or, so, or yet).
13. Please insert a space between numbers and their units of measurement (2 μm).
14. “Southern blot” should always be capitalised, whereas “western” and “northern” do not have to be.
15. “It’s” is the abbreviated form of “it is” (it’s absorbed), whereas “its” is possessive (its genotype).
16. Parentheses always have a space from the letters on the outside and no space on the inside (the fetal bovine serum (FBS) was) except for in chemical names (E2F1-(DE2F)-luc).
17. “That” introduces essential information, whilst “which” provides additional, non-essential information and must be preceded by a comma.
18. The apostrophe is used to indicate possession and to indicate omitted characters in contractions.
19. Square-brackets [] are non-mathematically used within quoted material and references. Parentheses () are used in general prose and can be used within themselves (round-brackets (parentheses) can be used like this).
20. The em dash (—) is used to indicate a parenthetical thought or interpolation, or to indicate an unfinished sentence when the speaker has been interrupted. They are not recommended for use in formal writing.
21. Words quoted from another source must be placed in double-quotation marks “”. Either single (British) or double (American) quotation marks can be used to differentiate a word from the surrounding text (mark with an “X” or ‘X’), but only when absolutely necessary.
22. Most acronyms are capitalised (NASA, PCR), whilst an abbreviation matches the capitalisation of the written word (Fig., pp.).
23. Parallelism: A balance of two or more similar phrases, clauses, or words (the solution was mixed, dried, and tested). The grammatical elements of parallel clauses must match. Parallelism improves the readability of manuscripts.
24. “Should”, “would”, or “could” take the verb “have” (I should have gone) and not “of”.
25. Avoid double negatives in formal writing.

Scientific Specific

1. Use “pH” with the unit before the number (pH 4), and only use “pH” once at the beginning of a list (buffered to pH 5, 7, and 9).
2. Abbreviate units when you are reporting a numerical value (mix for 4 h). Spell out the unit when used in a non-numerical context (measured in centimetres). When beginning a sentence with a unit and number, both must be written in full.
3. Use active verbs whenever possible; passive verbs require more space and deaden the writing.
4. Minimise your use of personal pronouns as they reduce the objectivity of the manuscript. Only use to distinguish who is performing the work described.
5. Use the past tense to refer to actual work completed by you or by others; use the present tense for generally accepted research or knowledge.
6. Avoid anthropomorphism: Only humans can diagnose or identify (“CT helped diagnose” or “CT was used to diagnose”, not “CT diagnosed”).
7. The use of slashes “/” to separate words can be confusing because they have multiple interpretations. Authors should avoid unless the meaning is absolutely clear.
8. Do not write “very unique” or “very novel” as they are not measured in degrees.
9. Numbers less than one must always begin with a zero (0.01 μm).
10. For ranges, use the word “to” or an en-dash “–” (not a hyphen).
11. Use “most” instead of “majority” unless you specifically mean “over 50%”.
12. Only use “significantly” when referring to statistically significant data, otherwise use “greatly” or “notably”.
13. Do not use the singular form of the verb with “data” or “media” (“data are expressed”, not “data is expressed”).
14. The plural of “pH” is “pH values” (not “pHs”).
15. A11 abbreviations in a manuscript must be consistent and defined at first mention.
16. When using “respectively”, ensure that you have two lists that match in number (the round, square and triangular balls were red, blue, and green, respectively).

Grammar

1. All pronouns must have an antecedent (the noun they replace) that they agree with in number, gender and person. There must be a clear antecedent and excessive use is to be avoided in formal writing.
2. Avoid beginning a sentence with an antecedent (e.g., “Its”) or a demonstrative pronoun (e.g., “this”).
3. The subjunctive mood should only be used to imply strong doubt (“If the results were accurate” suggests they are likely to be inaccurate).
4. Subjects joined by “and”, whether singular or plural, require a plural verb. Singular subjects joined by “or” require a singular verb. When singular and plural subjects are joined by “or”, the verb agrees with the nearest subject.
5. When a number is used to describe a single measurement, a singular verb is used (10 ml was added). However, if the subject is considered in separate parts, a plural verb is required (10 ml drops were added one by one).
6. The indefinite article “a” precedes a word beginning with a sounded consonant and “an” precedes a word beginning with a vowel sound.
7. The definite and indefinite articles should be used in formal writing; however, they may be partially excluded in headings, titles, figures, and lists.
8. Adverbs such as “only”, “almost”, “nearly”, “actually” and “also” must be placed as near as possible to the words they modify.
9. Avoid tautology: for example, 10 h in duration-10 h, ranging from 5 to 9-from 5 to 9, close proximity-proximity.
10. Avoid pleonasms: for example, are found to be in agreement-agree, give consideration to-consider, in order to-to.
11. When a sentence begins with a number, the number must be written in full.
12. Avoid using a split infinitive unless the sentence requires it to avoid awkwardness or confusion.

Vocabulary

1. “In contrast” is usually followed by “to” or “with” and requires a noun to follow it (in contrast to the number of). “By contrast” is usually followed or preceded by the subject of the sentence (by contrast, the number of).
2. “Between” is used to refer to distinct, individual items even if there are more than two of them (between you, me, and the doorknob). “Among” is used to refer to things that aren't distinct items or individuals (among us), and to indicate that something is part of or left out of a group (the pen was among the pencils).
3. Be aware that “lead” is the present tense form and “led” is the past tense form of the verb “to lead”. Do not confuse with the element lead.
4. Be aware of the differences between “to lay” (present tense, lays; past tense, laid) and “to lie” (present tense, lies; past tense, lay).
5. Be aware of the difference between “lose” (to lose the keys) and “loose” (the screw is loose).
6. Be aware that the noun “absorption” has the past tense “absorbed” and the gerund “absorbing”. Be careful to distinguish between “absorption” (the process of swallowing up or sucking in something) and “adsorption” (the process by which something adheres to the surface of something else without being assimilated into it).
7. Accurate vs precise: To be accurate simply means to be correct, whereas to be precise is to be correct to a highly defined degree.
8. Amount vs number: “Amount” relates to things that can be measured in bulk, i.e., a quantity of something, whereas “number” refers to things that can be counted.
9. Affect vs effect: “Affect” is a verb meaning “to have an influence on”. “Effect” is a noun. (The ph value affects the reaction. The effect of this is an increase in product.)
10. Percent vs percentage: “Percent” means one part in a hundred (40 percent of patients); “percentage” means a part of a whole expressed in hundredths (the percentage of cells).
11. Less vs fewer: Use less with mass nouns (ones you can’t count individually, i.e., “less applause”) and fewer with count nouns (ones you can count, i.e., “fewer cells”). Exceptions: use “less” to describe time, money, and distance.
12. Since vs because: They are interchangeable in that both imply a logical connection between two phrases; however, “since” additionally relates to time and must only be used when it is clear which of the two definitions it refers to.
13. Dose vs dosage: the “dose” is the specific quantity of an agent to be administered in a given instance, whereas the “dosage” is a broader term that includes the size of the dose and the intervals at which it is to be taken.
14. Avoid excessive or effusive language (insightful comments-comments; fairly well-well). This will cut down the word count and improve the readability of your manuscript.
15. Avoid imprecise language. In most cases, imprecise words can be deleted (very, fairly, a lot) or rephrased (roughly-approximately).
16. Different than, from, or of: “Different than” is grammatically incorrect, and whilst “different from” is the most formal phrase, “different to” is also acceptable in scientific writing.