English Grammar & Usage

Cards · 60

Subject-verb agreement: basic rule

A singular subject takes a singular verb, whereas a plural subject takes a plural verb.

Subject-verb agreement: compound subjects with 'and'

Two or more singular subjects joined by 'and' almost always require a plural verb.

Subject-verb agreement: subjects with 'either/or' or 'neither/nor'

The verb agrees with the subject closest to it.

Subject-verb agreement: collective nouns

In American English, collective nouns take singular verbs when acting as a unit, but plural verbs if members act individually.

Indefinite pronouns agreement: everyone, somebody, each

Pronouns like 'everyone', 'somebody', and 'each' are grammatically singular and require singular verbs.

Subject-verb agreement: intervening phrases

Phrases like 'as well as' or 'along with' coming between subject and verb do not change the subject's number.

Present simple vs. present continuous

Present simple expresses habits and general facts, while present continuous expresses actions currently in progress.

Stative verbs usage

Verbs expressing states, feelings, or perception (e.g., 'know', 'love') are generally not used in continuous tenses.

Past simple vs. present perfect

Use past simple for completed past events with specific times; use present perfect for past events linked to the present.

Present perfect: 'for' vs. 'since'

Use 'for' to indicate the duration of an ongoing period and 'since' to denote the specific starting point in time.

Past continuous vs. past simple with 'when' or 'while'

A continuous tense describes an ongoing background action interrupted by a shorter action in the simple past.

Past perfect tense usage

Use past perfect ('had' + past participle) to describe an action that happened before another past action.

Future forms: 'will' vs. 'be going to'

Use 'will' for spontaneous decisions or promises, and 'be going to' for preexisting plans or predictions based on evidence.

Subjunctive mood: hypothetical conditions

Use 'were' instead of 'was' for all persons in contrary-to-fact 'if' clauses (e.g., 'If I were you').

Subjunctive mood: mandative verbs

Verbs of demand or suggestion (e.g., 'insist', 'recommend') take a 'that'-clause with a base verb form.

Zero conditional

Formed with 'if/when' + present simple, present simple; used to express universal truths or scientific facts.

First conditional

Formed with 'if' + present simple, 'will' + base verb; used to express real or likely future possibilities.

Second conditional

Formed with 'if' + past simple, 'would' + base verb; used to talk about hypothetical or unreal present/future states.

Third conditional

Formed with 'if' + past perfect, 'would have' + past participle; expresses unreal conditions and outcomes in the past.

Mixed conditional

Combines past conditions with present results, typically 'if' + past perfect paired with 'would' + base verb.

Modal verbs: obligation with 'must' vs. 'have to'

'Must' usually expresses internal or personal obligation, while 'have to' indicates external rules or laws.

Modal verbs: 'should' vs. 'ought to'

Both express advice, duty, or expectation, but 'ought' requires 'to' before the infinitive verb.

Modal verbs: past deduction with 'must have' vs. 'can't have'

Use 'must have' for near-certainty that an event occurred; use 'can't have' to express certainty that it did not.

Passive voice formation and usage

Formed using 'be' + past participle; shifts focus from the performer of the action to the recipient.

Intransitive verbs in the passive voice

Intransitive verbs cannot take direct objects and therefore cannot be converted into the passive voice.

Gerund vs. infinitive after prepositions

Prepositions must always be followed by a gerund (-ing form), never a bare or to-infinitive.

Split infinitive rule

Placing an adverb between 'to' and the verb is standard in modern usage unless it makes the sentence awkward.

Pronoun case: subject vs. object pronouns

Use subject pronouns (I, he, they) as grammatical actors; use object pronouns (me, him, them) as objects.

Pronoun case in compound structures

Remove the other person mentally to test correctness (e.g., 'Give it to Bob and me' because 'Give it to me').

Pronoun case: predicate nominative

Traditionally, a pronoun following the linking verb 'to be' should be in the subjective case (e.g., 'It was I').

'Who' vs. 'whom'

Use 'who' when the pronoun acts as a subject; use 'whom' when it acts as an object of a verb or preposition.

Reflexive pronoun usage

Reflexive pronouns (myself, himself) must refer back to an antecedent in the same clause, not replace object pronouns.

Pronoun-antecedent agreement

A pronoun must match its referent noun in number and person; singular 'they' is standard for unspecified gender.

Indefinite articles: 'a' vs. 'an'

Use 'a' before consonant sounds and 'an' before vowel sounds, regardless of the initial written letter.

Definite article: 'the' with unique or specific nouns

Use 'the' when both speaker and listener know the specific referent, or when an entity is unique.

Zero article with plural and uncountable nouns

Omit articles when speaking about uncountable nouns or plural countable nouns in a general sense.

Order of cumulative adjectives

Adjectives follow: opinion, size, physical quality, shape, age, color, origin, material, type, purpose.

Coordinate adjectives and comma usage

Place commas between adjectives that independently modify the noun and can be separated by 'and'.

Comparative vs. superlative: two items vs. three or more

Use the comparative form (-er, more) for two entities; use the superlative form (-est, most) for three or more.

Absolute adjectives (e.g., 'unique', 'perfect')

Adjectives describing all-or-nothing states cannot logically take comparative or superlative modifiers.

Adverb vs. adjective after linking verbs

Linking verbs of sense (feel, look, smell, taste) take adjectives describing the subject, not adverbs.

Dangling modifier rule

An introductory modifying phrase must immediately precede the actual subject it intends to describe.

Misplaced modifier rule

Modifiers should sit as close as possible to the specific words they modify to avoid ambiguity.

Run-on sentences and comma splices

Two independent clauses cannot be joined by a comma alone; use a coordinating conjunction, semicolon, or period.

Coordinating conjunctions (FANBOYS) and commas

Place a comma before a coordinating conjunction only when it connects two full independent clauses.

Semicolon usage between independent clauses

Use a semicolon to connect two closely related independent clauses without a coordinating conjunction.

Colon usage for lists and explanations

A colon must be preceded by a complete independent clause introducing the list, quotation, or explanation.

Apostrophe for possessives: singular vs. regular plural

Add -'s to singular nouns to show possession; add only an apostrophe after regular plural nouns ending in -s.

'It's' vs. 'its'

'It's' is a contraction for 'it is' or 'it has'; 'its' is the possessive pronoun, which never takes an apostrophe.

Parallel structure in lists and series

All items in a list or joined by correlative conjunctions must share the same grammatical form.

Correlative conjunctions placement

Pairs like 'either/or' and 'not only/but also' must be followed by parallel grammatical structures.

Restrictive vs. non-restrictive relative clauses

Restrictive clauses are essential and take no commas; non-restrictive clauses add extra detail and need commas.

'That' vs. 'which' in relative clauses

In American English, 'that' introduces restrictive clauses, while 'which' introduces non-restrictive clauses.

Double negatives

Using two negative words in the same clause resolves logically to a positive, canceling the intended negation.

'Fewer' vs. 'less'

Use 'fewer' with plural countable items; use 'less' with singular uncountable nouns or collective amounts.

'Amount' vs. 'number'

Use 'amount' for uncountable bulk quantities and 'number' for separate, countable entities.

'Lie' vs. 'lay' in the present tense

'Lie' is intransitive meaning to recline; 'lay' is transitive meaning to set down and requires a direct object.

Past tense of 'lie' vs. 'lay'

The past tense of the intransitive verb 'lie' is 'lay'; the past tense of the transitive verb 'lay' is 'laid'.

'Affect' vs. 'effect'

'Affect' is typically a verb meaning to influence; 'effect' is typically a noun denoting a result.

Ending a sentence with a preposition

Ending a sentence with a terminal preposition is standard and acceptable English when avoiding awkward phrasing.