Verb tense in a sentence, or in a group of related sentences, should not change without a good reason. A good reason could be to indicate a change of time, for instance. Like in this example:
Pulp Fiction is a classic film that was made in 1994.
Unwarranted shifts in tense, like in the following sentence, can make your text confusing.
I enrolled in the business course because I wanted to take over my father’s business. However, after a few months I
start losing interest.
This would be an unwarranted shift from past to present and a revised version of this sentence would look like this:
I enrolled in the business course because I wanted to take over my father’s business. However, after a few months I started losing interest.
The verb start is now in the same tense as in the related sentence.
Unwarranted shifts don’t only occur from past to present, but also the other way around.
Shifts in voice can also occur, for instance from active to passive, or from passive to active. The following example shows an unwarranted shift from active to passive:
Walter Isaacson wrote a biography of Steve Jobs, and later a biography of Leonardo da Vinci
This awkward change in voice could be revised like this, by making the passive voice (was written) active (wrote):
Walter Isaacson wrote a biography of Steve Jobs, and later wrote a biography of Leonardo da Vinci.
There are instances where a shift in voice from active to passive within a sentence may be necessary, however, like here:
Although the students protested, the legal drinking age was raised.
In this case the shift from active (protested) to passive (was raised) keeps the focus on the students and the fact that they protested. Saying who raised the drinking age (for example, the government), in an active sentence would change the emphasis of the sentence here.
Mood indicates whether the writer is making a statement or asking a question, which is called the indicative mood. Issuing a command or making a request is a called the imperative mood, and expressing a wish or a hypothetical condition is called the subjunctive mood.
Shifting between moods also leads to awkward sentences, like in this example, where the sentence shifts from the imperative to the indicative mood for no reason.
Next, place the slide under the microscope, and
you should make sure to refocus the lens.
A revised version of this sentence would look like this:
Next, place the slide under the microscope, and be sure to refocus the lens.
Person indicates who is speaking (for instance first person I or we), second person (So, who is spoken to (you)), and who is spoken about (he, she, it and they), which is third person. Unwarranted shifts in person often occur between third and second person, like in this sentence:
someone buy s a house, you should compare mortgage rates.
Here is the revised sentence:
When you buy a house, you should compare mortgage rates.
Number indicates shifts between singular (for instance, words like it, business, or cell) and plural (they, them, businesses, or cells). Singular pronouns should refer to singular antecedents and plural pronouns should refer to plural antecedents, which is not the case in the following sentence
If a person does not exercise regularly,
they will not remain physically fit.
Here plural they refersto a singular noun, a person. The revised sentence should be this:
If a person does not exercise regularly, he or she will not remain physically fit.
Direct discourse reports the direct words of the speaker or writer using quotation marks and an identifying tag (for instance she says), like in this sentence:
My teacher said, ‘I want you to report to the principal’s office.’
Indirect discourse summarizes the words of the speaker of writer and no quotation marks are used. To introduce the reported words, that is often used in case of a statement. For questions, who, what, why, whether, how, or if are used. Here is an example:
My teacher said that he wanted me to report to the principal’s office.
Shifts from in direct to direct discourse often cause the sentence to be confusing. Like here:
During the speech, Jake Anderson strongly emphasised the regulations and said
I am in charge.