3.2 Common Sentence Errors


This section of Ch. 3 will cover the following topics:

  • subject-verb agreement
  • misplaced and dangling modifiers
  • parallel structure

Mistakes make a negative impression on a reader (and on a grade). Three common sentence errors are subject-verb agreement, modifier problems, and lack of parallel structure. By understanding parts of speech and sentence structure, these errors can be avoided.

Subject-Verb Agreement

“Subject-verb agreement” means the of a sentence and the of a sentence must agree with each other in number. A singular subject needs a singular verb, and a plural subject needs a plural verb. For example:

Singular: The cat jumps over the fence.
Plural: The cats jump over the fence.

Errors in subject-verb agreement are common, especially when the subject of the sentence is separated from the verb by lots of other words. However, if we isolate the prepositional phrases (remember: subjects and verbs never appear in prepositional phrases), then it’s easier to see if the subject and verb agree.

The students with the best grades in the school wins the academic awards.
The puppy under the table is my favorite.

“students” and “wins” do not agree, but “puppy” and “is” do agree.

Exercise 1

In your notebook, correct the errors in subject-verb agreement in the following sentences.

  1. My dog and cat chases each other in the house.
  2. The books in my library is the best I have ever read.
  3. There is the newspapers I was supposed to deliver.
  4. Some of the clothes is packed away in the attic.
  5. Crows in my white maple tree and on the electrical line is annoying.


A modifier is a word, phrase, or clause that clarifies or describes another word, phrase, or clause. Adjectives and adverbs are modifiers. Phrases and clauses can also work as modifiers.

Two common modifier errors are misplaced modifiers and dangling modifiers. When these errors occur, readers become confused trying to figure out what the writer means.

A misplaced modifier is too far from the word or words it modifies.

Misplaced modifiers make a sentence awkward and sometimes unintentionally funny. For example:

She wore a bicycle helmet on her head that was too large.

This seems to say her head was too large. The modifying phrase “that was too large” should be closer to the word “helmet.” The modifier is misplaced.

Corrected: She wore a bicycle helmet that was too large on her head.

Here is another example:

The patient was referred to a physician with stomach pains. (Does the doctor have stomach pains? The modifier “with stomach pains” is too far from the word “patient.”)

Corrected: The patient with stomach pains was referred to a physician.

Exercise 2

In your notebook, rewrite the following sentences correcting the misplaced modifiers.

  1. The young lady was walking the dog on the telephone.
  2. I heard there was a robbery on the evening news.
  3. Rolling down the mountain, the explorer stopped the rock with his foot.
  4. We are looking for a babysitter for our six-year-old who doesn’t smoke and owns a car.
  5. The teacher served cookies to the children wrapped in aluminum foil.
  6. Charlie spotted a stray puppy driving home from work.

Another modifier problem is what is called a “dangling modifier.”

A dangling modifier describes something that isn’t in the sentence.

When there is nothing for the modifier to modify, it is said to “dangle.” For example:

Riding in the sports car, the world whizzed by rapidly. (Who is noticing the world whizzing by? There is something missing. The modifier “riding in the sports car” is dangling.)

Corrected: When Farzad was riding in the sports car, the world whizzed by rapidly.

Exercise 3

Rewrite the following the sentences in your notebook and add any necessary information to correct the dangling modifiers.

  1. Playing a guitar in the bedroom, the cat was seen under the bed.
  2. Packing for a trip, a cockroach scurried down the hallway.
  3. While driving to the veterinarian’s office, the dog nervously whined.
  4. Piled up next to the bookshelf, I chose a romance novel.
  5. Chewing furiously, the gum fell out of my mouth.

Parallel Structure

When something is parallel to something else, they are similar in form. For example, two parallel lines look like this:


Parallelism in writing is when a similar structure is used in related words, phrases or clauses.

For example, these three phrases have parallel structure:

in the pool, in the forest, in the book

They feel balanced. Also, they are easy to read and remember.

Now look at these word groups:

in the pool, forests are green, book shelf

They are different from each other in structure. Notice how jagged it feels to read them, and they are more difficult to remember.

Parallel structure creates rhythm and balance within a sentence. An unbalanced sentence sounds awkward. Read the following sentences aloud:

Kelly had to iron, do the washing, and shopping before her parents arrived.

Driving a car requires coordination, patience, and to have good eyesight.

Swimming in the ocean is much tougher than a pool.

All of these sentences contain faulty parallelism. The construction is clunky and confusing. In the first example, three different verb forms are used (“had to iron,” “do the washing,” “shopping”). In the second example, the writer begins with nouns (“coordination,” “patience”), but ends with a phrase (“to have good eyesight”).  In the third sentence, the writer is comparing an action (“swimming”) with a thing (“a pool”).

Here are the same sentences with correct parallelism:

Kelly had to do the ironing, washing, and shopping before her parents arrived. (The verbs have the same structure.)

Driving a car requires coordination, patience, and good eyesight. (The three qualities are all written as nouns.)

Swimming in the ocean is much tougher than swimming in a pool. (One action is being compared with another action.)

When sentences use parallel structure, they sound more pleasing. Repetition of the pattern also minimizes the work a reader has to do to understand the sentence.

Exercise 4

In your notebook, revise the following sentences to create parallel structure.

  1. I would rather work at a second job to pay for a new car than a loan.
  2. How you look in the workplace is just as important as your behavior.
  3. Indian cuisine is tastier than the food of Great Britain.
  4. Jim’s opponent in the ring was taller, carried more weight, and not as strong.
  5. Working for a living is much harder than school.


  • A verb must agree with its subject in number.
  • Misplaced and dangling modifiers make sentences difficult to understand.
  • Parallelism creates rhythm and balance in writing by using the same grammatical structure.


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