1.2 Punctuation and Mechanics

Introduction: The Role of Punctuation

Punctuation and mechanics questions on the SHSAT assess your ability to use punctuation marks correctly to clarify meaning and ensure sentence coherence. Incorrect punctuation can create run-on sentences, comma splices, or fragmented thoughts. This section reviews the essential rules for commas, semicolons, colons, apostrophes, and commonly confused words that you will encounter on the exam.

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Comma Rules

Commas are the most frequently tested punctuation mark on the SHSAT. They are used to separate ideas, set off parenthetical information, and prevent ambiguity.

1. Items in a Series (The Oxford Comma)

Use commas to separate three or more items in a list. The comma before the conjunction (and, or) is called the Oxford comma, and it is required in standard written English on the SHSAT.

• Example: The student purchased a calculator, a notebook, and three pens.

2. Introductory Clauses and Phrases

When a dependent clause or a long prepositional phrase begins a sentence, it must be followed by a comma.

• Example: Although the weather was freezing, the track team completed their morning practice.
• Example: During the long winter of 2024, the researchers gathered temperature data. Note: If the independent clause comes first, you generally do not need a comma before the dependent clause (e.g., The track team completed their morning practice although the weather was freezing).

3. Coordinate Adjectives

Coordinate adjectives are two or more adjectives that modify the same noun independently. Use a comma to separate them.

• The Test: If you can insert the word and between the adjectives and reverse their order without changing the meaning, they are coordinate and require a comma.
• Example: The large, heavy box was difficult to lift. (You can say large and heavy or heavy, large box.)
• Counter-Example: The bright yellow house was recently painted. (You cannot say bright and yellow house or yellow bright house. Therefore, no comma is used.)

4. Non-Essential (Non-Restrictive) Clauses and Phrases

A non-essential clause provides extra information that is not critical to the core meaning of the sentence. If you remove it, the sentence still makes sense. Non-essential clauses must be set off with commas. Essential (restrictive) clauses, which are critical to the sentence's meaning, do not use commas.

• Non-Essential: My math teacher, who loves to play chess, started a school tournament. (Removing "who loves to play chess" doesn't change the fact that the math teacher started a tournament.)
• Essential: The student who won the chess tournament received a trophy. (Removing "who won the chess tournament" makes the sentence vague; we don't know which student received the trophy. No commas are used.)

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Semicolons and Colons

Semicolons and colons have distinct, formal rules. The SHSAT often tests whether you can distinguish between them.

1. Semicolons

A semicolon is primarily used to connect two independent clauses that are closely related in thought. The semicolon acts as a bridge and replaces a period or a comma plus coordinating conjunction (FANBOYS).

• Rule: The clauses on both sides of the semicolon must be complete, independent sentences.
• Example: The school library is a quiet place to study; many students gather there after school.

Semicolons are also used before conjunctive adverbs (like however, therefore, consequently) that connect two independent clauses, followed by a comma.

• Example: The chemistry exam was exceptionally challenging; however, class averages remained high.

Finally, use semicolons to separate items in a list if the items themselves already contain commas.

• Example: The tour stops in Albany, New York; Boston, Massachusetts; and Providence, Rhode Island.

2. Colons

A colon is used to introduce a list, an explanation, or a quote.

• Rule: The clause before the colon must be an independent clause (a complete sentence). The information after the colon does not have to be an independent clause.
• Example: The backpack contained three essential tools: a compass, a map, and a whistle.
• Incorrect: The backpack contained: a compass, a map, and a whistle. (The clause before the colon is not a complete sentence.)

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Apostrophes

Apostrophes serve two main purposes: showing possession and indicating contractions.

1. Possessive Nouns

• Singular Nouns: Add 's (e.g., the boy's desk, the bus's route).
• Plural Nouns Ending in S: Add only an apostrophe at the end (e.g., the boys' desks, the teachers' lounge).
• Plural Nouns Not Ending in S: Add 's (e.g., the children's museum, the women's team).

2. Contractions vs. Possessive Pronouns

The SHSAT frequently tests homophones that involve apostrophes. Remember that possessive pronouns never use apostrophes.

• its (possessive) vs. it's (it is / it has)
• their (possessive) vs. they're (they are) vs. there (location)
• whose (possessive) vs. who's (who is / who has)
• your (possessive) vs. you're (you are)

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Commonly Confused Words

In addition to punctuation, the SHSAT tests your ability to distinguish between words that sound alike but have different meanings.

• Affect vs. Effect: Affect is usually a verb meaning to influence (e.g., The weather will affect our plans). Effect is usually a noun meaning the result (e.g., The effect of the medicine was immediate).
• Than vs. Then: Than is used for comparisons (e.g., She is taller than her brother). Then indicates time or sequence (e.g., We went to the park, and then we went home).
• Accept vs. Except: Accept is a verb meaning to receive (e.g., I accept the offer). Except is a preposition meaning excluding (e.g., Everyone went except John).
• Principal vs. Principle: Principal refers to a person of high authority, like a school leader, or an amount of money (e.g., The principal spoke at assembly). Principle is a fundamental truth or rule (e.g., It is against my principles to cheat).