Parts of Speech and Word Formation for UPSC CDS English

intermediate 18 min read

Concept

Every word in an English sentence has a job. The label for that job is its part of speech — and the crucial point that CDS examiners exploit relentlessly is this: the same word can do different jobs in different sentences. The word "finance" is a noun in "the finance department" but a verb in "they could not finance the project." The word "right" is an adjective in "the right answer" but an adverb in "turn right." The word "first" is an adjective in "the first runner" but an adverb in "who came first?"

Think of it like a military rank that depends on context, not on the person. A Colonel is a Colonel on the parade ground, but in a civilian meeting he might be introduced as "a defence advisor." Same person — different role in that context. Similarly, the same word wears different grammatical uniforms depending on its position and function in the sentence.

The eight traditional parts of speech are: Noun, Pronoun, Verb, Adjective, Adverb, Preposition, Conjunction, Interjection. To this list, CDS questions frequently test two special verb-derived forms: Gerunds (verb-ing forms acting as nouns) and Participles (verb-ing or verb-ed forms acting as adjectives). These two are the most common confusion points in CDS papers.

Here is the single principle that should govern every identification question you attempt: Do not label a word by its dictionary category. Label it by what it does in the specific sentence in front of you. Ask — what does this word modify or name? If it names something, it is functioning as a noun. If it modifies a noun, it is functioning as an adjective. If it modifies a verb, adjective, or another adverb, it is functioning as an adverb. If it introduces a noun phrase and shows a relationship, it is a preposition.

That one habit — reading for function, not form — will resolve almost every identification question CDS sets.


Deep Dive

The Core Eight: What Each Class Does

Nouns name persons, places, things, qualities, or concepts. In a sentence, nouns appear as subjects, objects, or complements. The CDS trap: abstract nouns ("heights," "beauty," "fear") and verbal nouns that don't look like typical nouns. Test: can you put "the" in front of it? Can it follow a preposition? If yes, it's behaving as a noun.

Verbs express action or state. The key structural signal: a main verb follows a modal auxiliary (can, could, will, would, must, shall, may, might). If a word follows "could not" and takes an object, it is the main verb — regardless of whether that same word doubles as a noun elsewhere.

Adjectives modify nouns or pronouns and answer the questions which?, what kind?, how many? They typically sit before the noun they modify (attributive: "protective clothing") or after a linking verb (predicative: "it is obligatory"). Words ending in -ory, -ary, -ive, -al, -ful, -less, -ous are almost always adjectives.

Adverbs modify verbs, adjectives, or other adverbs, answering how?, when?, where?, to what degree? The most reliable structural test: find the verb in the sentence, then ask whether the underlined word tells you something about that verb. If yes — adverb. The -ly suffix is a strong signal, but words like "first," "right," "hard," "fast," "early" are adverbs without -ly when they modify verbs.

Prepositions link a noun/pronoun to the rest of the sentence, showing relationships of time, place, cause, or manner. They always introduce a noun phrase — the object of the preposition. "During our winter holidays" — "during" links the time frame to the main clause. Classic CDS trap: "during," "despite," "concerning," "regarding" look unfamiliar but are prepositions.

Pronouns substitute for nouns. Conjunctions link clauses or words. Interjections express emotion and are grammatically independent. These three rarely appear as identification questions in CDS; examiners prefer the richer confusion territory of the first five.

Gerund vs. Participle vs. Verb: The -ing Battleground

This is the single most tested distinction in CDS parts-of-speech questions. Here is how to separate the three uses of -ing forms:

Gerund: The -ing word functions as a noun. It is a subject, object, or complement. Test — can you replace it with a pronoun like "it" or "this"? "Swimming is good for health" → "It is good for health." The swap works. Gerund confirmed.

Present Participle (Adjective use): The -ing word modifies a noun. "The aching muscles" — "aching" tells you which muscles. It functions as an adjective. Another form: participial phrase attached to a noun — "The man running outside is my brother." Here "running" modifies "man."

Verb (part of tense): The -ing word is part of a continuous tense, always paired with an auxiliary "be" form. "My arms are aching terribly." Here "aching" is the main verb of the predicate, paired with "are." The underlined word "terribly" modifies this verb — that question is about "terribly," not "aching," but recognising the verb structure is essential to identifying what "terribly" does.

The Context-Shift Trap: Same Word, Different Class

| Word | As Adjective | As Adverb | As Noun | |------|-------------|-----------|---------| | first | the first arrival | who came first | the first of January | | right | the right turn | turn right | know your rights | | hard | a hard surface | study hard | — | | early | an early start | arrive early | — | | last | the last train | she arrived last | at last |

CDS sets these context-shift traps repeatedly. The strategy: underline the word, find its target (what it is attached to semantically), then name the part of speech.

Word Formation Patterns

Parts of speech are also tested through suffixes that signal word class:

"Obligatory" ends in -ory — an adjective suffix. Even if you didn't know the word's meaning, the suffix alone points to adjective. This is a useful fallback when vocabulary fails you.


Memory Tricks & Shortcuts

substitutionThe Replacement Test for Gerunds

When an -ing word appears as the subject or object of a sentence, replace it with the pronoun "it" or the phrase "this activity." If the sentence still makes grammatical sense, the -ing word is a gerund (noun). "Swimming is good for health" → "It is good for health." Works. Gerund confirmed. "The swimming child laughed" → "The it child laughed." Breaks. Not a gerund — it is a participle (adjective). Standard approach of analysing the full grammatical structure takes about 30 seconds; this swap test takes 5 seconds.

patternVerb-Finder First, Then Modifier-Label

In any identification question, your first move is always to find the main verb of the sentence — not the underlined word. Once you have the verb, ask: does the underlined word point to (modify) the verb directly? If yes, adverb. Does it point to a noun? Adjective. Does it name something and sit in the subject/object slot? Noun. Does it follow a modal auxiliary and take an object? Verb. This 4-step decision costs 3 steps fewer than running through all eight parts of speech in sequence. Reduces per-question time from roughly 40 seconds to 15 seconds.

patternSuffix Shortcut for Unknown Words

If you encounter an unfamiliar word (a word like "obligatory" may trip up some test-takers), scan its ending. -ory, -ary, -ive, -al, -ous, -ible → almost certainly adjective. -ly ending on a word that isn't a noun → almost certainly adverb. -tion, -ment, -ity → noun. -ize, -ify → verb. This does not replace contextual analysis but works as a 3-second filter when you are stuck. In the CDS paper, this eliminates at least one wrong option in roughly 70% of unfamiliar-word identification questions.

patternThe Preposition Slot Test

A preposition always introduces a noun phrase — never stands alone at the end of a clause or modifies a verb directly. To confirm a word is a preposition, check: (1) Does a noun phrase follow it? (2) Does the noun phrase become its object? "During our winter holidays" — "our winter holidays" is the noun phrase; "during" governs it. If a word introduces a clause (with a subject + verb following), it is a conjunction, not a preposition. This distinction matters for words like "although," "while," "after" — which can be either. The test takes 2 steps versus the 6-step approach of checking every possible class.

eliminationModal + Bare Infinitive = Verb

Any word that immediately follows a modal auxiliary (can, could, will, would, shall, should, may, might, must, need, dare) and is not "not" or an adverb is the main verb of the predicate — regardless of its other uses. "Could not finance" — strip the modal and the negative: what remains is "finance." It takes an object ("the project"). It is a verb. This eliminates the noun reading of "finance" in one move. Identifying verb this way: 2 steps. Running through all four options without this rule: 5-7 steps.


Fast-Solving Framework

When you see a parts-of-speech identification question in the CDS hall, run this sequence:

Step 1 — Find the main verb. Locate the finite verb of the main clause. Do not confuse -ing forms or infinitives with the main verb unless they are part of a tense.

Step 2 — Locate the underlined word's target. What does the underlined word attach to semantically? A noun? A verb? Another adjective? Nothing (stands alone)?

Step 3 — Apply the function label. Modifies noun → adjective. Modifies verb/adjective/adverb → adverb. Names something, occupies subject/object position → noun. Follows modal, takes object → verb. Introduces noun phrase showing relationship → preposition.

Step 4 — Check for traps. Is this a common context-shift word (right, first, hard, last, early)? Is this an -ing form — and if so, does the substitution test confirm gerund? Is there a modal auxiliary nearby confirming a verb reading?

Step 5 — Eliminate. Rarely do you need all four options. Steps 1-4 typically narrow you to one or two candidates. Pick the one that matches the function identified in Step 3.

Allocate no more than 25 seconds per identification question. If you cannot resolve it in that time, mark your best elimination choice and move on.


Solved PYQs

Why this question: "First" is one of the most frequently misidentified words in English grammar — it appears as an adjective ("the first chapter") far more often in daily reading, so most test-takers default to that label without checking function.

Previous Year Questionपिछले वर्ष का प्रश्न2026
Who came first in the race?
  1. Preposition
  2. Adjective
  3. Adverb
  4. Article
Solutionसमाधान
In the sentence 'Who came first in the race?', the word 'first' describes how or when someone 'came' - it modifies the verb 'came', indicating the manner or order of the action. Words that modify verbs are adverbs. Here 'first' functions as an adverb of order/sequence describing the action of coming. Therefore, the correct word class is adverb.

Solving path: Find the main verb — "came." Now ask: does "first" modify the noun (there is no noun near it) or modify the verb "came"? It modifies "came" — it tells you the order in which someone came. That makes it an adverb of sequence/order. The answer is Adverb. Time using the verb-finder-first method: 10 seconds.


Why this question: "Obligatory" is tested as a vocabulary-plus-grammar item. Even if you know the meaning, you need to correctly assign the word class — and the -ory suffix is the shortcut that bypasses vocabulary entirely.

Previous Year Questionपिछले वर्ष का प्रश्न2026
It is obligatory for all employees to wear protective clothing.
  1. Noun
  2. Adjective
  3. Adverb
  4. Participle
Solutionसमाधान
The word 'obligatory' describes the quality of something being required or mandatory. In this sentence, it describes the state of wearing protective clothing - characterizing it as compulsory. Words that describe or qualify nouns/situations are adjectives. 'Obligatory' is an adjective meaning required by rule or law. Therefore, the correct word class is adjective.

Solving path: Apply the suffix test — "obligatory" ends in -ory, a classic adjective suffix. Confirm contextually: it appears after the linking verb "is" in a predicative position, describing the state of wearing protective clothing. Predicate adjective confirmed. The answer is Adjective. Time: 8 seconds.


Why this question: "Right" is the classic context-shift trap. It is adjective in "the right answer," noun in "human rights," but adverb in "turn right." CDS examiners know that most aspirants associate "right" with adjective.

Previous Year Questionपिछले वर्ष का प्रश्न2026
Turn right at the end of the street.
  1. Adjective
  2. Adverb
  3. Noun
  4. Preposition
Solutionसमाधान
In the sentence 'Turn right at the end of the street', the word 'right' modifies the verb 'turn', indicating the direction in which to turn. Words that modify verbs are adverbs. Here 'right' functions as an adverb of direction. While 'right' can be used as a noun or adjective in other contexts, in this sentence it modifies the verb 'turn' and therefore is an adverb.

Solving path: Find the main verb — "turn." Does "right" modify "turn"? Yes — it tells you the direction of turning, answering "how/where to turn." It modifies a verb, so it is an adverb of direction. The answer is Adverb. Time: 10 seconds.


Why this question: The gerund-versus-participle-versus-verb distinction is tested directly here. The distractors include "Participle" and "Verb," which are the two most tempting wrong answers for -ing forms.

Previous Year Questionपिछले वर्ष का प्रश्न2026
Swimming is good for health.
  1. Participle
  2. Verb
  3. Noun
  4. Gerund
Solutionसमाधान
In the sentence 'Swimming is good for health', the word 'Swimming' is the subject of the verb 'is'. When an -ing form of a verb is used as a noun (especially as a subject or object), it is called a gerund. Here 'Swimming' functions as the subject of the sentence and represents the activity of swimming as a noun-like concept. Therefore, the correct word class is gerund.

Solving path: Apply the replacement test — "Swimming is good for health" → "It is good for health." The swap works. "Swimming" occupies the subject slot and can be replaced by "it." This is a gerund. Note: a participle would modify a noun (e.g., "the swimming child"). A verb requires an auxiliary "be" form (e.g., "is swimming"). The answer is Gerund. Time: 12 seconds.


Why this question: This tests whether you can identify an adverb of degree, and whether you misread "terribly" as having something to do with the adjective "bad" or conflate it with "terrible" (adjective).

Previous Year Questionपिछले वर्ष का प्रश्न2026
My arms are aching terribly.
  1. Noun
  2. Adjective
  3. Adverb
  4. Participle
Solutionसमाधान
In the sentence 'My arms are aching terribly', the word 'terribly' modifies the verb 'aching', describing the intensity or degree of the aching. Words that modify verbs and end in -ly typically indicate adverbs of manner or degree. 'Terribly' here functions as an adverb of degree, telling how the arms are aching. Therefore, the correct word class is adverb.

Solving path: Find the main verb — "aching" (continuous tense: "are aching"). "Terribly" modifies "aching" — it tells you the degree of intensity of the aching. Modifies a verb → adverb. The -ly suffix reinforces this. The answer is Adverb. Time: 8 seconds.


Why this question: "Finance" is a classic dual-class word. In "the finance minister" it is a noun (or noun adjunct). The trap here is that most people encounter "finance" as a noun in headlines and administrative language, not as a verb.

Previous Year Questionपिछले वर्ष का प्रश्न2026
The local council could not finance the project as planned.
  1. Noun
  2. Verb
  3. Adverb
  4. Participle
Solutionसमाधान
In the sentence 'The local council could not finance the project as planned', the word 'finance' follows the modal 'could not' and takes 'the project' as its object. This shows that 'finance' is being used as the main verb of the sentence, meaning 'to provide funding for'. While 'finance' can be a noun in other contexts, here it clearly functions as a verb. Therefore, the correct word class is verb.

Solving path: Apply the modal rule — "could not" is a modal auxiliary + negative. The word immediately following (after stripping "not") is "finance." It takes "the project" as a direct object. Main verb following modal + taking direct object = verb. The answer is Verb. Time: 10 seconds.


Why this question: "During" is a time-preposition that students sometimes confuse with a conjunction ("while") because it introduces a time-related phrase. The test: does a noun phrase or a clause follow it?

Previous Year Questionपिछले वर्ष का प्रश्न2026
We met a lot of interesting people during our winter holidays.
  1. Conjunction
  2. Preposition
  3. Article
  4. Participle
Solutionसमाधान
In the sentence 'We met a lot of interesting people during our winter holidays', the word 'during' shows the relationship between the meeting and the time period (winter holidays). It indicates time and connects a noun phrase to the rest of the sentence. Words that show relationships of time, place, or direction between nouns and other elements are prepositions. Therefore, 'during' is a preposition.

Solving path: What follows "during"? — "our winter holidays," a noun phrase (no subject-verb structure inside it). A word that introduces a noun phrase and shows a time relationship is a preposition. If a clause (subject + verb) had followed, it would be a conjunction. The answer is Preposition. Time: 10 seconds.


Common Mistakes


Related Topics

Practice on SarkariRise

Sign up + get 3 free mocks →