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Verbal Reasoning
Grammar & Sentence Correction

Grammar & Sentence Correction: The Errors That Show Up Most

17 min read2,175 questions available
In this lesson20 sections

Good grammar is quiet: when it's right, nobody notices; when it's wrong, everybody does. On the Civil Service Exam, grammar and sentence-correction questions ask you to catch and fix the errors that trip up even fluent speakers — the mismatched verb, the dangling phrase, the comma doing a job too big for it. The reassuring truth is that a small set of error types accounts for the vast majority of these questions. Learn to spot those, and you'll fix sentences quickly and confidently — on the exam and in your own writing.

1. Lesson Overview

Grammar and sentence-correction questions ask you to identify an error in a sentence, choose the correct version, or fill a blank with the right verb form. Rather than testing obscure rules, they concentrate on a handful of high-frequency error types: subject-verb agreement, verb tense, pronoun use, parallel structure, modifiers, and punctuation between clauses.

On the Civil Service Exam, these items are a substantial part of the Verbal section, and the skill also powers Paragraph Organization and clear official writing. Because the same error types repeat, targeted practice pays off far more than trying to review "all of grammar."

The difficulty is intermediate. Many errors sound fine because they mirror casual speech, so the exam rewards a reader who checks the structure deliberately — matching each verb to its true subject, each pronoun to its antecedent, and each clause to correct punctuation. This lesson gives you that checklist.

2. Learning Objectives

After completing this lesson you will be able to:

  • Apply subject-verb agreement, including tricky cases (each/every, neither/nor, collective nouns).
  • Choose the correct verb tense and form for the subject and the time signal.
  • Match pronouns to their antecedents and avoid ambiguous reference.
  • Maintain parallel structure in lists and comparisons.
  • Fix misplaced and dangling modifiers.
  • Correct comma splices and run-on sentences.
  • Distinguish commonly confused words (its/it's, their/there/they're, fewer/less, who/whom).
  • Avoid the "sounds fine" trap by checking structure, not just ear.

3. Prerequisites

You should be comfortable with:

  • Parts of speech — noun, verb, pronoun, adjective, adverb, conjunction.
  • Subject and verb — identifying who/what does the action and the action word.
  • Basic sentence structure — what makes a complete sentence (a subject + a verb expressing a full thought).
  • Singular vs. plural nouns and verbs.

A quick refresher on the foundation: a clause has a subject and a verb. An independent clause expresses a complete thought and could stand alone as a sentence ("The rain stopped"). A dependent clause cannot ("when the rain stopped"). Much of grammar — especially punctuation between clauses — depends on telling these apart. Keep the idea of "complete thought vs. incomplete" in mind throughout.

4. Why This Topic Matters

Correct grammar is a daily, career-long asset:

  • Professional writing. Reports, memos, emails, and letters in any civil-service role must be clear and error-free to be taken seriously.
  • Credibility. Fair or not, grammatical errors make writing (and the writer) look careless; clean grammar signals competence.
  • Clarity. Good grammar prevents genuine misunderstandings — a misplaced modifier can change who did what.
  • Reading. Understanding sentence structure helps you parse complex legal and official language.
  • Everyday communication. From social media to job applications, correct grammar helps you be understood and respected.

The exam tests grammar because clear writing is a core workplace skill — and errors have real consequences.

5. Core Concepts

We'll cover the high-frequency error types in the order they most often appear.

Subject-verb agreement

The verb must match the subject in number (singular/plural), even when words come between them.

Incorrect: "The list of items are on the table." (The subject is "list" — singular — not "items.") Correct: "The list of items is on the table."

The trick is that a phrase like "of items" sits between the subject and verb to lure you into matching the nearer noun. Find the true subject and ignore the in-between words.

Trickier cases:

  • Each, every, either, neither are always singular: "Each of the students has finished" (not "have").
  • Either…or / neither…nor — the verb agrees with the nearer noun: "Neither the manager nor the employees were informed" (agrees with "employees").
  • Collective nouns (team, committee, family) are usually singular when acting as one unit: "The committee has decided."

Analogy: Think of the subject and verb as dance partners who must match steps. Distracting words in between are other dancers on the floor — don't accidentally match your partner's steps to a stranger's.

Verb tense and form

Match the verb to the subject and to the time signal in the sentence.

  • Simple present (habits): "I walk to school every day." (I/you/we/they use the base form.)
  • Third-person present adds -s/-es: "He exercises regularly."
  • Present continuous (happening now): "At the moment, I am revising."
  • Simple past (completed action): "Yesterday, she walked to work."

Time-clue words tell you the tense: "every day" → present habit; "at the moment/now" → continuous; "yesterday/last week" → past.

Tense consistency: don't shift tense mid-sentence without reason.

Incorrect: "She walked to the store and buys milk." (past then present) Correct: "She walked to the store and bought milk."

Pronoun agreement and reference

A pronoun must match its antecedent in number and be clear about what it refers to.

Number: "Each employee must submit his or her report" (formal writing treats the singular "each" as singular). Ambiguous: "Maria told Sarah that she passed." (Who passed — Maria or Sarah?) Rewrite to make it clear.

Also mind case: use the subject pronoun (I, he, she, we, they) for the doer, and the object pronoun (me, him, her, us, them) for the receiver. "Between you and me" (object of "between"), not "between you and I."

Parallel structure

Items in a list or comparison should share the same grammatical form.

Incorrect: "She enjoys reading, to write, and painting." (mixes -ing forms with an infinitive) Correct: "She enjoys reading, writing, and painting."

The moment you write a series, make every item the same shape — all -ing words, or all nouns, or all infinitives.

Misplaced and dangling modifiers

A descriptive phrase should sit next to the word it describes.

Misplaced: "Running down the street, the bus was missed by John." (implies the bus was running) Correct: "Running down the street, John missed the bus."

Dangling: "After finishing the report, the printer broke." (the printer didn't finish the report) Correct: "After finishing the report, I found that the printer broke."

Whenever a sentence starts with an -ing or -ed phrase, the thing right after the comma must be the one doing that action.

Comma splices and run-ons

A comma splice joins two complete sentences with only a comma — too weak on its own. A run-on joins them with nothing at all.

Incorrect (splice): "The rain stopped, we went outside." Fix options: add a conjunction — "The rain stopped, so we went outside"; use a semicolon — "The rain stopped**;** we went outside"; or make two sentences — "The rain stopped. We went outside."

The rule: two independent clauses need a conjunction (and, but, so, or…) with the comma, or a semicolon, or a period.

Commonly confused words

The exam loves near-twins:

  • its (possessive) vs. it's (it is): "The dog wagged its tail." / "It's raining."
  • their / there / they're: possession / place / "they are."
  • fewer (countable) vs. less (uncountable): "fewer cars," "less traffic."
  • who (subject) vs. whom (object): "Who called?" / "To whom did you speak?"
  • affect (verb) vs. effect (noun): "The rain will affect the game." / "The effect was a delay."
  • between (two) vs. among (more than two).

The "sounds fine" trap

Many errors mirror everyday speech, so they sound correct. "The list of items are…" sounds acceptable but is wrong. Train yourself to check the structure — subject-verb match, pronoun reference, clause punctuation — rather than trusting your ear alone.

With the checklist built, let's picture, tabulate, and drill.

6. Visual Learning Suggestions

  • [Illustration Suggestion] Subject-verb bridge. A sentence with the subject and verb linked by an arch, and the in-between phrase ("of items") drawn underneath the arch, showing it doesn't affect the match.
  • [Illustration Suggestion] Parallel train tracks. A list drawn as three parallel rails, all the same shape (reading/writing/painting), with a broken rail marking the odd one out ("to write").
  • [Illustration Suggestion] Modifier pointing finger. An opening phrase with an arrow that must point to the noun right after the comma; a "wrong" version shows the arrow hitting the bus instead of John.
  • [Illustration Suggestion] Clause connectors. Two complete-sentence blocks that can be joined by a comma-plus-conjunction bridge, a semicolon bridge, or split by a period — but never a bare comma.

7. Formula Library

Grammar runs on rules rather than formulas:

RuleCorrect form
Subject-verb agreementverb matches the true subject's number
Each/every/either/neithersingular verb
Neither…nor / either…orverb agrees with the nearer noun
Third-person presentadd -s/-es (he walks)
Tense consistencykeep the same tense unless time changes
Pronoun casesubject (I/he) does; object (me/him) receives
Parallel structureall list items share one form
Modifier placementnext to the word it describes
Two clausescomma + conjunction, semicolon, or period

8. Pattern Recognition

When you see…Check for…
a phrase between subject and verbsubject-verb agreement (ignore the phrase)
"each," "every," "neither," "either"singular verb
a blank with a time word ("every day," "now," "yesterday")the matching tense
a pronoun far from its nounclear, matching reference
a list (A, B, and C)parallel structure
an opening -ing/-ed phrase + commathe right noun right after the comma
two complete thoughts joined by a commacomma splice — fix the join
its/it's, their/there, fewer/less, who/whomthe correct twin

9. Problem-Solving Framework

Step 1 — Find the subject and verb, ignoring any words between them, and check agreement. ↓ Step 2 — Check the verb tense against the sentence's time clues and keep it consistent. ↓ Step 3 — Trace each pronoun to a clear, number-matching antecedent. ↓ Step 4 — Scan lists for parallel structure and opening phrases for correct modifier placement. ↓ Step 5 — Check clause punctuation (no bare comma between two complete thoughts) and confused-word pairs.

Why Step 1 matters most: subject-verb agreement is both the most common error and the most disguised (by in-between phrases). Always locate the true subject first.

10. Worked Examples

Format: identify the correct sentence or the needed correction.

Beginner

Example 1. Which is correct: (a) "The box of chocolates are on the table." (b) "The box of chocolates is on the table." Solution: (b). The subject is "box" (singular); "of chocolates" is a distractor. Difficulty: ★☆☆☆☆

Example 2. Fill in: "He ___ to the gym every morning." (go / goes) Solution: goes — third-person singular adds -s. Difficulty: ★☆☆☆☆

Intermediate

Example 3 (each = singular). Correct the verb: "Each of the players ___ a uniform." (have / has) Solution: has — "each" is always singular. Difficulty: ★★☆☆☆

Example 4 (neither…nor). Choose the verb: "Neither the teacher nor the students ___ ready." (was / were) Solution: were — the verb agrees with the nearer noun, "students." Difficulty: ★★★☆☆

Example 5 (parallelism). Fix: "The job requires typing, filing, and to answer calls." Solution: "The job requires typing, filing, and answering calls." (all -ing forms) Difficulty: ★★★☆☆

Advanced

Example 6 (misplaced modifier). Fix: "Covered in mud, Ana washed the dog." Thinking: The opening phrase should describe the muddy one — the dog, not Ana. Solution: "Ana washed the dog, which was covered in mud." (or "Covered in mud, the dog was washed by Ana.") Difficulty: ★★★★☆

Example 7 (comma splice). Fix: "The meeting ended early, everyone went home." Solution: "The meeting ended early, so everyone went home." (or a semicolon/period.) Difficulty: ★★★☆☆

Example 8 (pronoun case). Choose: "The prize was shared between Ben and ___." (I / me) Solution: me — object of "between." Difficulty: ★★★☆☆

Civil Service Exam Level

Example 9 (agreement with a collective noun). Choose: "The committee ___ reached a decision." (have / has) Solution: has — the committee acts as one unit here. Difficulty: ★★★★☆

Example 10 (tense consistency). Fix: "He opened the door and sees a stranger." Solution: "He opened the door and saw a stranger." (keep the past tense) Difficulty: ★★★☆☆

Example 11 (confused words). Choose: "The new rule will ___ everyone's schedule." (affect / effect) Solution: affect — a verb meaning "to influence." ("Effect" is the noun result.) Difficulty: ★★★★☆

Example 12 (dangling modifier). Fix: "While driving to work, the radio suddenly stopped." Thinking: The radio wasn't driving; name the driver. Solution: "While driving to work, I noticed the radio suddenly stopped." (or "While I was driving to work, the radio suddenly stopped.") Difficulty: ★★★★★

11. Exam Tricks

  • Distractor between subject and verb. "The quality of the products is high" — the plural "products" tempts a plural verb, but the subject is "quality."
  • "Sounds fine" errors. Casual-sounding sentences ("Each of them have…") are often wrong. Check the rule, not the ear.
  • Opening-phrase bait. After an -ing/-ed opener, the exam puts the wrong noun right after the comma to create a dangling modifier.
  • Twin words. its/it's, their/there/they're, affect/effect, fewer/less — these are quick, guaranteed items; memorize them cold.
  • Comma-splice disguise. Two complete thoughts joined by a comma look smooth but are wrong; test whether each half could stand alone.

12. Common Mistakes

  • Matching the verb to the nearest noun instead of the true subject.
  • Forgetting "each/every/either/neither" are singular.
  • Overlooking a misplaced or dangling modifier that describes the wrong noun.
  • Breaking parallel structure in a list or comparison.
  • Joining two complete sentences with only a comma (a comma splice).
  • Confusing twin words (its/it's, affect/effect, fewer/less, who/whom).

13. Shortcuts

  • Cross out the middle. Mentally delete any phrase between the subject and verb to check agreement cleanly.
  • Read the opener's owner. After an -ing/-ed opening phrase, jump straight to the noun after the comma — it must be the doer.
  • Two-halves test for comma splices: if both sides of the comma are complete sentences, the comma alone is wrong.
  • Base form for I/you/we/they; add -s for he/she/it in the simple present — a one-second verb check.
  • Twin-word flashcards: drill its/it's, their/there/they're, affect/effect — they're free marks.

14. Memory Techniques

  • "Find the true subject." Ignore the words between it and the verb.
  • "Each is one." Each/every/either/neither always take a singular verb.
  • "The opener owns the next noun." Prevents dangling modifiers.
  • "Parallel lists march in step." Keep every item the same form.
  • "Two complete thoughts need a strong join." Conjunction, semicolon, or period — never a lone comma.

15. Real Civil Service Exam Strategy

  • Time: a sentence-correction item takes 20–40 seconds; recognizing the error type is most of the work.
  • Scan for the usual suspects in order: agreement, tense, pronoun, parallelism, modifier, punctuation.
  • Don't trust your ear alone — many wrong answers sound natural. Verify with the rule.
  • Eliminate answers that fix one error but create another; the best choice is clean on every count.
  • Bank the twin-word items quickly (its/it's, affect/effect) to save time for trickier questions.

16. Practice Questions

Choose the correct option or the needed fix.

Easy

  1. "The group of tourists (is / are) waiting outside."
  2. "She (walk / walks) to the market on Sundays."

Medium

  1. "Neither the players nor the coach (was / were) satisfied."
  2. "Each of the rooms (has / have) a window."

Hard

  1. Fix: "He likes hiking, swimming, and to run."
  2. Fix: "Tired after the trip, the sofa looked inviting to Marco."

Challenge

  1. "The effect / affect of the new law surprised everyone." (choose the correct word)
  2. Fix the comma splice: "The store was closed, we came back later."
  3. "To (who / whom) should I address the letter?"
  4. Fix the tense: "She finishes her homework and went to bed."

Answers and Explanations

  1. is. Subject is "group" (singular).
  2. walks. Third-person singular.
  3. was. Agrees with the nearer noun, "coach" (singular).
  4. has. "Each" is singular.
  5. "He likes hiking, swimming, and running." Parallel -ing forms.
  6. "Tired after the trip, Marco found the sofa inviting." Marco was tired, not the sofa.
  7. effect. Here it's the noun (the result).
  8. "The store was closed, so we came back later." (or semicolon/period).
  9. whom. Object of "to."
  10. "She finished her homework and went to bed." Keep both verbs past tense.

17. Summary

Grammar and sentence correction reward spotting a small set of repeat errors. Match each verb to its true subject (ignoring in-between phrases), remembering that each/every/either/neither are singular and neither…nor agrees with the nearer noun. Keep tense consistent and matched to time clues; give every pronoun a clear, number-matching antecedent and the right case. Keep lists parallel, place modifiers next to what they describe, and never join two complete thoughts with a bare comma (use a conjunction, semicolon, or period). Master the twin words (its/it's, affect/effect, fewer/less, who/whom). Above all, check the structure rather than trusting your ear — that's how you catch the errors that "sound fine."

18. Cheat Sheet

Error typeFix
Subject-verbmatch the true subject
Each/every/either/neithersingular verb
Neither…noragree with nearer noun
Tensekeep consistent; match time clue
Pronounclear antecedent; right case
Parallelismsame form for all list items
Modifierbeside the word it describes
Comma splice+ conjunction / semicolon / period
Twinsits/it's, their/there/they're, affect/effect, fewer/less, who/whom

19. Frequently Asked Questions

How do I find the subject when there are many words? Ignore any phrase starting with "of," "with," "along with," etc., between the subject and verb. The subject is the main noun the sentence is really about ("the list of items").

Why is "Each of them have" wrong? "Each" is grammatically singular, so it takes a singular verb: "Each of them has." The plural "them" is a distractor.

When do I use a semicolon? To join two complete, closely related sentences without a conjunction: "The rain stopped; we went outside." Both sides must be able to stand alone.

How do I remember affect vs. effect? "Affect" is usually a verb (an Action); "effect" is usually a noun (the End result). "The rain will affect the game; the effect was a delay."

What's a dangling modifier? An opening descriptive phrase whose real subject is missing or misplaced, so it seems to describe the wrong thing: "While driving, the radio stopped" (the radio wasn't driving). Name the doer right after the comma.

20. Mastery Checklist

  • ☐ I can match a verb to its true subject despite in-between phrases.
  • ☐ I treat each/every/either/neither as singular.
  • ☐ I keep verb tense consistent and matched to time clues.
  • ☐ I give pronouns clear antecedents and correct case.
  • ☐ I keep lists and comparisons parallel.
  • ☐ I place modifiers next to the words they describe.
  • ☐ I fix comma splices with a conjunction, semicolon, or period.
  • ☐ I know the common confused-word pairs cold.

Tick them all and grammar becomes a quick, dependable strength — and your professional writing will read as clean and competent.

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