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Grammar and Usage Unit 6: Modifiers, parallelism and verb tense

Clear sentences put modifiers next to what they describe, keep items in a series in the same form, and don't jump between tenses.

Covers: Misplaced and dangling modifiers, parallel structure, consistent verb tense, active vs passive voice

Study guide

A modifier is a word or phrase that describes something, and it should sit next to the word it modifies. A misplaced modifier is in the wrong spot, creating confusion: "She almost drove her kids to school every day" (did she almost drive?) should be "She drove her kids to school almost every day." A dangling modifier has nothing in the sentence to modify: "Walking to school, the rain started" makes it sound like the rain was walking. Fix it by naming the doer right after the phrase: "Walking to school, I got caught in the rain."

Parallel structure means using the same grammatical form for items in a series or comparison: "She likes to run, to swim and to bike," or "She likes running, swimming and biking," but not "to run, swimming and to bike." Parallelism also applies to paired constructions like not only…but also, either…or, and both…and, and to comparisons ("Reading a book is better than watching TV").

Verb tense should stay consistent unless the timeline actually changes. Don't switch from past to present in the middle of a narrative without a reason. Use the perfect tenses to show order: the past perfect (had finished) for an action completed before another past action. When writing about literature, use the present tense.

In the active voice the subject does the action ("The chef cooked the meal"); in the passive voice the subject receives it ("The meal was cooked by the chef"). Active voice is usually clearer, more direct and shorter. Passive voice is useful when the doer is unknown or unimportant ("The window was broken"), and it's common in scientific writing.

In conditional sentences, match the tenses of the two clauses. For a real possibility, use present + will: "If it rains, we will stay home." For an imagined situation, use past + would: "If I had a car, I would drive." After when, before, after, until, as soon as and by the time, use the present tense even when the meaning is future: "I will call you when I arrive," not "when I will arrive."

Use the past progressive (was or were + -ing) for an action in progress when another past action interrupted it: "I was reading when the phone rang." Use the simple present for habits and general truths ("She walks to school every day"). Compare like with like. Write "Her grades are higher than her brother's" or "than those of her brother," not "higher than her brother." In the second version, grades are being compared with a person.

Some verbs require a specific form of the verb that follows. After let and make, use the base form ("made him leave"); help takes either form ("helped me move" or "helped me to move"). After want, decide and plan, use an infinitive ("decided to leave"). After enjoy, avoid and finish, use an -ing form ("enjoyed leaving early").

Key ideas

• A modifier should sit right next to the word it describes.
• A dangling modifier describes something not named in the sentence.
• Parallel structure: items in a list or comparison use the same grammatical form.
• Keep verb tense consistent unless the time actually changes.
• Active voice ("The dog chased the cat") is usually clearer than passive.

Formulas and rules

Common mistakes

• "Walking to school, the rain started." (The rain wasn't walking.)
• Mixing forms in a list: "I like hiking, to swim, and bikes."

Words to know

Dangling modifier

A phrase that doesn't clearly describe any word in the sentence.

Parallel structure

Using the same grammatical form for items in a series.

Active voice

The subject does the action.

Passive voice

The subject receives the action.

Misplaced modifier

A modifier placed next to the wrong word: fix by moving it next to what it describes.

Modifier

A word or phrase that describes something.

Squinting modifier

A modifier that could describe the word before or after it.

Parallelism with correlatives

Not only…but also, either…or: match the forms after each part.

Consistent verb tense

Don't switch tenses without a reason.

Past perfect

had + past participle: an action completed before another past action.

Literary present

Write about literature in the present tense.

When to use passive voice

When the doer is unknown or unimportant.

Sample practice questions

5 more questions like these, from level 1 to 5, are in the practice set.