Sentence Improvement Questions for CDS

What Sentence Improvement Tests

Each question gives you a sentence with an underlined portion. Four options follow: three alternatives and one 'No improvement' option. Your job is to pick the option that makes the sentence grammatically correct, idiomatic, and clear. The error is always in the underlined part only. Do not look for problems elsewhere in the sentence.

• The underlined part may contain a grammar error, wrong word choice, or awkward phrasing.
• Option D is usually 'No improvement' — do not avoid it blindly; it appears 20-30% of the time.
• Read the full sentence first, then focus on the underlined portion.
• If no option sounds clearly better, choose 'No improvement'.
• Eliminate obviously wrong options first — this saves time.

Subject-Verb Agreement

This is the single most tested grammar rule in CDS Sentence Improvement. The verb must agree with the subject in number (singular/plural). Common traps include collective nouns, indefinite pronouns, and subjects separated from verbs by long phrases.

• Collective nouns (team, committee, jury) take singular verb in Indian/British usage: 'The committee has decided.'
• Indefinite pronouns (each, every, either, neither, anyone, nobody) always take singular verb.
• Words joined by 'along with', 'as well as', 'together with' — verb agrees with the FIRST subject.
• Either/Or, Neither/Nor — verb agrees with the subject CLOSER to the verb.
• 'The number of' takes singular verb; 'A number of' takes plural verb.

Tense Consistency

CDS frequently tests whether the tense in the underlined part matches the tense of the rest of the sentence. A common error is mixing past and present tense in the same sentence without logical reason. Also watch for the correct use of perfect tenses.

• Past Perfect (had + V3) is used for the earlier of two past actions: 'She had left before he arrived.'
• Present Perfect (have/has + V3) is used with 'just, already, yet, ever, never, since, for'.
• Simple Past is used with specific past time expressions: 'yesterday, last week, in 1990'.
• Never use Present Perfect with specific past time: NOT 'I have gone there yesterday'.
• If the sentence gives a historical or general truth, use Simple Present even in reported speech.

Prepositions and Idiomatic Usage

Wrong preposition choice is a classic CDS trap. Many verbs and adjectives are paired with fixed prepositions — these are called collocations or idioms. You cannot change them logically; they must be memorised. The exam tests whether you know the correct preposition that goes with a particular verb or adjective.

• Differ FROM (not 'than' or 'with'): 'This differs from that.'
• Agree WITH a person; Agree TO a proposal; Agree ON a point.
• Comply WITH, conform TO, oblivious OF/TO, immune TO, blind TO.
• Interested IN, good AT, angry WITH a person / angry AT a thing.
• Married TO (not 'with'): 'She is married to a doctor.'

Articles — A, An, The

Article errors are subtle but appear regularly. 'A' and 'An' are used with singular countable nouns mentioned for the first time. 'The' is used for specific or previously mentioned nouns, superlatives, and unique things. 'An' is used before words with a vowel SOUND, not just vowel letters.

• An + vowel sound: 'an hour' (h is silent), 'an MBA', 'an honest man'.
• A + consonant sound: 'a university' (sounds like 'yoo'), 'a European'.
• Use 'The' before unique nouns: the sun, the moon, the Prime Minister.
• No article before proper nouns, languages, meals (generally): 'He had lunch.'
• The + superlative: 'She is the best student.' Always.

Parallelism and Comparisons

Parallelism means that items in a list or comparison must be in the same grammatical form. CDS tests this frequently when sentences use 'and', 'or', 'but', 'not only...but also', 'either...or', 'both...and'. Faulty comparison is another common trap where you compare unlike things.

• Parallel structure: 'She likes singing, dancing, and to paint' — WRONG. Should be 'singing, dancing, and painting'.
• Not only...but also: both parts must have the same structure.
• Faulty comparison: 'Her score is better than Ram' — WRONG. Should be 'better than Ram's'.
• Compare like with like: people with people, things with things.
• Use 'other' when comparing within the same group: 'She is taller than any OTHER girl in class.'

Modifiers and Dangling Participles

A modifier must be placed next to the word it describes. A dangling participle is when the introductory phrase does not logically refer to the subject of the main clause. CDS tests this through sentence improvement options where one option fixes the illogical attachment.

• Dangling: 'Walking down the street, the trees looked beautiful.' — trees cannot walk.
• Correct: 'Walking down the street, I found the trees beautiful.'
• Misplaced modifier: 'She only eats vegetables' vs 'She eats only vegetables' — meaning changes.
• Introductory participial phrase always refers to the grammatical subject of the main clause.

• Automatically avoiding 'No improvement' — many aspirants never choose it out of fear. It is correct 20-30% of the time. Trust it when you cannot find a real error.
• Changing the verb to agree with a nearby noun instead of the actual subject. Example: 'The quality of the mangoes ARE good' — the subject is 'quality', so it should be 'is'.
• Confusing 'since' and 'for' — 'since' is used with a point in time, 'for' is used with a duration: 'since 2010' vs 'for ten years'.
• Thinking 'more better' or 'most tallest' are emphatic forms — they are always wrong. Never double a comparative or superlative.
• Replacing the correct preposition with a logical-sounding one. 'He insisted to go' sounds right but is wrong — it should be 'insisted on going'.

• PAST trick for tenses: Point of time = Simple Past, Action still relevant = Present Perfect, Sequence of past events = Past Perfect.
• SACENA for subject-verb traps: Separated subjects, Along with, Collective nouns, Either-or/Neither-nor, Number of (the vs a), Any indefinite pronoun — each needs singular verb.
• The FANBOYS rule for parallelism: For, And, Nor, But, Or, Yet, So — whatever follows one side of these conjunctions must match the other side grammatically.
• Vowel SOUND not vowel LETTER for An/A — say the word aloud. 'A uniform' (yoo-niform), 'An hour' (ow-er). Your ear decides, not your eyes.

• CDS English typically has 20 Sentence Improvement questions out of 120. That is about 17% of the paper — high priority. Allocate roughly 15-18 minutes for this section.
• Recent CDS papers (2022-2024) show heavy repetition of subject-verb agreement and tense errors. Preposition questions have also increased. Spend extra revision time on these two.
• The difficulty is low to medium. These are not trick questions — they test standard rules. A student who has revised 15 core grammar rules can score 80%+ here.
• When two options look very similar, focus on the smallest difference — usually a preposition, article, or one verb form. That tiny detail is the answer.
• Do not spend more than 40-45 seconds per question. If you are unsure, mark 'No improvement' and move on. Come back if time permits.