7 Grammar

Pronouns replace nouns. In this replacement, the antecedent must be clear and the pronoun must agree with the antecedent in number and gender.Note: The possessive pronoun its should not be confused with the contraction it's (see also , Punctuation, Apostrophe, Possessive Pronouns).Care must be taken to use the correct case of personal pronouns: subjective (the pronoun is the subject of the phrase or clause) or objective (the pronoun is the object of the phrase or clause).She was assigned to the active intervention group. (She is the subject.) Collect all the samples and give them to her. (Her is the object.) ...Less

Relative pronouns (who, whom, whose, that, and which) introduce a qualifying clause.Who is used as a subject and whom as an object. The examples below illustrate correct usage.Give the award to whomever you prefer. [Objective case: whomever is the object of the verb prefer.] Give the award to whoever will benefit most. [Subjective case: whoever is the subject of will benefit.] Whom did you consult? [Objective case: whom is the object of consult.] Who was the consultant on this case? [Subjective case: who is the subject of the sentence.] He is one of the patients whom Dr Rundle is treating. ...Less

A sentence must have at minimum a subject and a verb; it also usually contains modifiers. Sentence fragments, which lack a subject or a verb, should not be used in scientific or technical writing (except within the structured abstract; see , Manuscript Preparation, Abstract). Occasionally, writers of prose and poetry use sentence fragments intentionally, for effect.Her affect signaled depression. Utter depression.In scientific writing, these fragments are likely to be unintentional and are definitely inappropriate. ...Less

Parallel construction may also present a series or make comparisons. In these usages, the elements of the series or of the comparison should be parallel structures, eg, nouns with nouns, prepositional phrases with prepositional phrases.Note: Avoid the use of nor when the first negative is expressed by not or no.Fetuses with congenital diaphragmatic hernia who were stillborn would not have been included in this study or [not nor] in many previously published studies. But: Fetuses with congenital diaphragmatic hernia who were stillborn would not have been included in this study, nor would they have been included in other trials. [Nor is ...Less

In elliptical constructions involving the verb (ie, the second verb is omitted because it is understood), if the number of the subject changes, the construction is incorrect. ...

Although some authorities may still advise the avoidance of split infinitives, this proscription a holdover from Latin grammar, wherein the infinitive is a single word and cannot be split has been relaxed. In some cases, moreover, clarity is better served by the split infinitive. ...Less

The predicate noun is the complement of a subject; it identifies, describes, or renames the subject. When the subject and predicate noun differ in number, follow the number of the subject in selecting the singular or plural verb form.Avoid this by rephrasing: Study results were most affected by interhospital variations in severity of illness. ...Less

Subjects and complements should agree in number.The child can take off his own shoes. We asked trial participants to return their pill dispensers.However, when the complement is shared by all constituents of the plural subject, it remains singular.The authors were asked to revise their paper. All study sites obtained approval from their institutional review board. Investigators inserted a catheter into the study participants' pulmonary artery. ...Less

The subject and verb must agree in number; use a singular subject with a singular verb and a plural subject with a plural verb. Unfortunately, this simple rule is often violated, especially in complex sentences.Plural nouns take plural verbs and singular nouns take singular verbs, even if a phrase ending in a plural noun follows a singular subject or if a phrase ending in a singular noun follows a plural subject.A review of all patients with grade 3 tumors was undertaken in the university hospital. [The subject in this sentence is review. Ignore all modifying prepositional phrases that follow a ...Less

Tense indicates the time relation of a verb: present (I am), past (I was), future (I will be), present perfect (I have been), past perfect (I had been), and future perfect (I will have been). It is important to choose the verb that expresses the time that is intended. It is equally important to maintain consistency of tense.The present tense is used to express a general truth, a statement of fact, or something continuingly true.He discovered enzymes RNA polymerases that directly copy [not copied] the messages encoded in DNA.For this reason, the present tense is often used to refer to ...Less