SAT Grammar Rules

Subject and verb punctuation

"Subject and verb should NOT be separated by punctuation
Examples:
""The dog, barks loudly"" is INCORRECT
""The dog barks loudly"" is CORRECT"

Internal punctuation

Punctuation (especially commas, dashes, or brackets) within a single item in a list or phrase, often used to add extra information or clarify meaning

Complex series

List of items where at least 1 item has internal punctuation

Complex series grammar rules

"1. Semicolons used instead of commas to separate main items in series to avoid confusion, commas are only used as internal punctuation (to provide more details or clarification) within main items. Using only commas causes confusion

• Examples:
• Correct: ""She visited Paris, France; Rome, Italy; and Berlin, Germany.""
• Incorrect: ""She visited Paris, France, Rome, Italy, and Berlin, Germany."" (Too many commas make it confusing.)

2. Final item listed in complex series still introduced by preceding conjunctions (such as and, or, etc)

• Examples: 
• Correct: ""The conference featured speakers from Austin, Texas; Portland, Oregon; and Montreal, Canada.""
  
• Incorrect: ""The conference featured speakers from Austin, Texas; Portland, Oregon; Montreal, Canada.""
  

"

Comma splice

Where a comma is incorrectly used to join 2 independent clauses (clauses⸺subject + predicate (something describing subject, often has verb)⸺with complete meaning that make sense on their own and can act as standalone sentences)

Modifying noun phrase

"Group of words without a main verb that describe or give more information about a noun in the next clause/part of a sentence, can be appositive or descriptive
Usually placed at start of the sentence, always precedes the noun directly, and is separated from noun with a comma
1. Appositive modifying noun phrase: renames the subject (e.g. ""A renowned artist, Wigard creates tiny sculptures."")
2. Descriptive modifying noun phrase: highlights traits of the subject (e.g. ""Made of gold strands, the sculpture shimmered.""

If the subject after the comma isn’t what the phrase describes, it’s wrong! Always check logical connection.

"

Finite verb

Verbs that show tense (past, present, future), and which can function as the main verb of a clause or sentence.

Finite verb grammar rules

1. There can only be 1 main verb finite verb in a sentence unless joined by a conjunction
   2. Using 2 finite verbs in the same clause without proper conjunction is grammatically incorrect
   

Nonfinite verbs

Verbs that do not show tense and cannot serve as a sentence's main verb but which can serve as modifiers

Noninfinite verbs include: 
1. Present participles (-ing verbs, often used in supplementary phrases); e.g. running
2. Past participles (-ed verbs); e.g. studied
3. Infinitives (to + verb); e.g. to run 

Modifier

Word, phrase, or clause that provides additional information about another element in a sentence; often to describe, clarify, or limit meaning

Modifiers include:
1. Adjectives to modify nouns and pronouns
2. Adverbs to modify verbs, adjectives, or other adverbs
3. Phrases, including preopositional, participial (participial phrases are groups of words containing past or present participles and which can function as adjectives to modify a noun or pronoun), infinitive, etc
4. Clauses; dependent clauses can act as adjectives/adverbs

Supplementary (non-restrictive) phrases

Phrases that add extra information about a noun but which can be removed without changing the core meaning

Supplementary (non-restrictive) phrases grammar rules

1. Set off and separated from main sentence through commas, dashes, or parentheses
   2. Typically uses nonfinite verbs (e.g. present or past participles) 
   3. Interrupting phrases (e.g. supplementary participial phrases) MUST be separated from main sentence through proper punctuation and must have nonfinite verbs 
   
   KEY TAKEAWAY:
   1. ONLY nonfinite verbs (present -ing and past -ed participles) can be used for supplementary phrases
   2. Only 1 finite verb per clause unless properly joined with conjunctions
   3. Supplementary non-restrictive modifiers must be set off with commas

When should commas be used to set off supplementary elements?

"Use commas for:

• Adverbs (e.g. though, however): ""They are hardly pristine, though;…""
• Non-essential phrases: ""Donne's works, much admired, had…""

"

What is a comma splice, and how do you fix it?

"Comma splices are where 2 independent clauses are incorrectly joined together with commas

Solve by:

• Adding conjunction (e.g. ""independent clause 1, and independent clause 2"")
• Using a semicolon (e.g. ""independent clause 1; independent clause 2""

"

When should you use a semicolon?

"When connecting 2 related independent clauses, NEVER use semicolon between clauses and phrases 

e.g.: ""The location was agreed upon; establishing the spot was divisive.""

Or can also be used to show contrast between 2 clauses and/or join 2 thematically contrasting independent clauses

e.g: ""They are hardly pristine; many chondrites are damaged"""

When should you use a colon?

"To introduce explanations and lists, not for contrast

examples:

• Correct: ""She had one goal: to win.""
• Incorrect for contrast: ""They agreed: they disagreed.""

"

"How does though function after a comma vs. as a subordinator"

"Comma + though: contrasts prior clause (e.g.  (""They are pristine, though;…"")
Subordinator: Starts dependent clause (""…though they are damaged"")."

"How do you find the subject for verb agreement"

"Ignore prepositional phrases 

e.g. in ""The shape of the buildings…""; the subject is not the buildings themselves but the shape so the correct verb would be ""is"" (matches singular subject) not ""are"" (incorrect verb that would be used if we confuse the plural part (buildings) from the prepositional phrase as an element of the subject. 
"

How should past participles function in supplementary phrases?

"As adjectives offset by commas

e.g: ""His works, admired during his lifetime, were forgotten."""

"What’s a run-on, and how do you fix it?"

Two independent clauses without punctuation/conjunction. Fix with:

• Semicolon, comma + conjunction, or period.

Past participle

"Past-tense verb form often ending in -ed, -en, or as an irregular verb (verbs that do not follow regular -ed, -en, or -d rules when transformed from present to past tense, they have unpredictable patterns and must be memorised; e.g. ""go"" becomes ""gone"")

Past participle uses:

• Perfect tenses (e.g. has eaten)
• Passive verb (e.g. was admired)
• Adjective (e.g. the broken vase)

"

Perfect tense

Verb form to show an action was completed before a specific time; often follows this format:
has/have/had + past participle

Passive verb

"Verb form where subject receives the action instead of performing it, often follows this format: 
be verb (is/are/was/were) + past participle 
e.g. ""The data was analysed by the team"" or ""Chondrites are considered pristine""

Passive voice/verb omit actors if unimportant"

Subordinator

Subordinating conjunction; word that introduces a dependent clause and which shows its relationship with the main clause (e.g. because, though, although, if, since, etc)

Subordinator vs conjunctive adverb

"subordinators (e.g. though) create dependent clauses
e.g. ""Though they are damaged, chondrites are useful.""
conjunctive adverbs (e.g. however) link independent clauses
e.g. ""Chondrites are damaged; however, they are useful."""

Past participles and subordinators pro tip

"

• Past participles in supplementary phrases are offset by commas:
  ""The theory, disproven in 2020, was once popular.""
• Subordinators often trigger comma rules:
  ""Although the data exists, it’s unpublished.""

"

Restrictive phrase

Essential description/information that modifies a noun without commas

Participial phrase

Phrase starting with present participle (-ing verb) or past participle (-ed/-en verb) which functions as an adjective to modify a noun or pronoun. 
Adds description to a sentence without needing a subject; acts as description NOT main action
Can appear at beginning, middle, or end of sentence

Verb forms in participial phrases

In participial phrases that modify the noun, use nonfinite present participles (i.e. -ing verb forms) 

if verb describes subject and is not the main action, it's likely a verb in a participial phrase; if verb is preceded by a comma and describes the subject rather than being the main action; it's probably a -ing verb (i.e. a nonfinite present participle)! 

-ing nonfinite present participles can describe nouns anywhere
only -s finite verbs ca be the main action/verb of a sentence

SUMMARY:

• -ING = describing verb
• -S = main action verb

SAT Trick:
If the verb:

1. Comes after subject
2. Describes (not acts)
   → Use -ING

If the verb:

1. is main action verb
2. does not describe subject

→ use -s or another finite verb

Nonfinite past participle phrases

Phrase that contains a past particple verb but acts as an adjective/adverb modifying a nounclause and does NOT function as a main verb or contain verbs that function as the main verb
Act as supplementary modifiers for a noun
Adds description without creating a new clause 

Supplementary modifiers

"Phrases set off by commas often provide extra description. They must logically modify the nearest noun without disrupting the sentence’s grammar

• Correct: ""The car, designed in 1910, sold for millions.""
• Incorrect: ""The car, it was designed in 1910, sold…"" (repeats the subject).

SAT Trick: If a choice adds a subject/verb (""it was""), it’s likely wrong.
"

Parallel Structure in modifiers

"Descriptions in a list or series must use parallel forms (all participles, all adjectives, etc.).

• Correct: ""The artistry, prized by collectors and admired by historians, is rare.""
• Incorrect: ""The artistry, prized by collectors and historians admire it, is rare.""

Why It’s Tested: SAT checks for consistency in grammatical forms.

Study Tip: For SAT Writing, always ask:

1. Is this a complete clause or a modifier?
2. Does the punctuation correctly separate ideas?
3. Are verb forms parallel/logical?

"