9. Shifts

Just as you can change position to view a scene from different vantage points, in your writing you can change the time or perspective. However, shifting tense or point of view unconsciously or unnecessarily within a passage creates ambiguity and confusion for readers.

9a Maintain consistency in verb tense

tense: The time when the action of a verb did, does, or will occur

In a passage or an essay, use the same verb tense unless the time changes.

INCONSISTENT The driver yelled at us to get off the bus, so I ask him why, and he tells me it is none of my business.
CONSISTENT PRESENT The driver yells at us to get off the bus, so I ask him why, and he tells me it is none of my business.
CONSISTENT PAST The driver yelled at us to get off the bus, so I asked him why, and he told me it was none of my business.
9b If the time changes, change the verb tense

To write about events in the past, use past tense verbs. To write about events in the present, use present tense verbs. If the time shifts, change tense.

I do not like the new television programs this year. The comedies are too realistic to be amusing, the adventure shows don’t have much action, and the law enforcement dramas drag on and on. Last year the programs were different. The sitcoms were hilarious, the adventure shows were action packed, and the dramas were fast paced. I prefer last year’s reruns to this year’s shows.

The time and the verb tense change appropriately from present (do like, are, don’t have, drag) to past (were, were, were, were) back to present (prefer), contrasting this year’s present with last year’s past programming.

NOTE: When writing about literature, the accepted practice is to use present tense verbs to summarize what happens in a story, poem, or play. When discussing other aspects of a work, use present tense for present time, past tense for past, and future tense for future.

Steinbeck wrote “The Chrysanthemums” in 1937. [Past tense for past time]

In “The Chrysanthemums,” Steinbeck describes the Salinas Valley as “a closed pot” cut off from the world by fog. [Present tense for story summary]

9c Maintain consistency in the voice of verbs

For more on using active and passive voice, see 3m.

Shifting unnecessarily from active to passive voice may confuse readers.

INCONSISTENT My roommates and I sit up late many nights talking about our problems. Grades, teachers, jobs, money, and dates are discussed at length.
CONSISTENT My 809roommates and I sit up late many nights talking about our problems. We discuss grades, teachers, jobs, money, and dates at length.
9d Maintain consistency in person

See 5 and also A5 in the Quick Editing Guide for more on pronoun forms.

Person indicates your perspective as a writer. First person (I, we) establishes a personal, informal relationship with readers as does second person (you), which brings readers into the writing. Third person (he, she, it, they) is more formal and objective. In a formal scientific report, second person is seldom appropriate, and first, if used, might be reserved for reporting procedures. In a personal essay, using he, she, or one to refer to yourself would sound stilted. Choose the person appropriate for your purpose, and stick to it.

INCONSISTENT College students need transportation, but you need a job to pay for the insurance and the gasoline.
CONSISTENT College students need transportation, but they need jobs to pay for the insurance and the gasoline.
INCONSISTENT Anyone can go skydiving if you have the guts.
CONSISTENT Anyone can go skydiving if he or she has the guts.
CONSISTENT You can go skydiving if you have the guts.
9e Maintain consistency in the mood of verbs

For examples of the three moods of verbs, see 3n–3p.

Avoid shifts in mood, usually from indicative to imperative.

INCONSISTENT Counselors advised students to register early. Also pay tuition on time. [Shift from indicative to imperative]
CONSISTENT Counselors advised students to register early. They also advised them to pay their tuition on time. [Both indicative]
9f Maintain consistency in level of language

To impress readers, writers sometimes inflate their language or slip into slang. The level of language should fit your purpose and audience throughout an essay. For a personal essay, use informal language.

INCONSISTENT I felt like a typical tourist. I carried an expensive digital camera with lots of icons I didn’t quite know how to decode. But I was in a quandary because there was such a plethora of picturesque tableaus to record for posterity.

Instead of suddenly shifting to formal language, the writer could end simply: But with so much beautiful scenery all around, I couldn’t decide where to start.

For an academic essay, use formal language.

INCONSISTENT Puccini’s Turandot is set in a China of legends, riddles, and fantasy. Brimming with beautiful melodies, this opera is music drama at its most spectacular. It rules!

Cutting the last sentence avoids an unnecessary shift in formality.