SAT English: When to Use a Hyphen (and Not Get Tricked!)

Hey there, SAT warriors! 🚀 If you’re prepping for the SAT, you probably know that punctuation matters—a lot. Commas, semicolons, and colons get plenty of attention, but today, we’re diving into two little punctuation marks that can be surprisingly tricky: hyphens (-) and dashes (—).

The hyphen may be small, but it has a big job, and knowing how to use it correctly can help you avoid sneaky SAT grammar traps. The dash, on the other hand, is its cooler, longer cousin and works differently in sentences. So, let’s break it all down and make sure you never get confused again!

Did You Know? Fun Facts About SAT English: When to Use a Hyphen!

1️⃣ Hyphens Can Change Meaning! – A small-business owner owns a small business, but a small business owner might just be short! 😆

2️⃣ Not All Prefixes Need Hyphens! – "Rebuild" is correct, but "re-enter" needs a hyphen to avoid confusion.

3️⃣ Compound Modifiers Follow a Rule! – Hyphenate high-energy student but not the student is high energy.

4️⃣ Numbers Need Hyphens! – "Twenty-five questions" is correct, but "one hundred" doesn’t need a hyphen.

5️⃣ Dashes Are NOT Hyphens! – A hyphen joins words, while a dash adds emphasis—totally different! 🚀

SAT English: When to Use a Hyphen

Hyphens aren’t just there to make words look fancy. They actually serve specific purposes in English grammar. On the SAT, incorrect hyphen use can lead to subtle (but costly) errors. Here’s when you should use a hyphen:

1. Hyphens in Compound Modifiers (Adjective + Noun Pairs)

If two or more words work together as a single adjective before a noun, they should be hyphenated.

✅ Correct: She bought a well-written book.
❌ Incorrect: She bought a well written book.

✅ Correct: He’s a high-energy student.
❌ Incorrect: He’s a high energy student.

👉 But watch out! If the modifier comes after the noun, you don’t use a hyphen.

✅ Correct: The book is well written.
✅ Correct: The student is high energy.

2. Hyphens in Numbers & Fractions

Hyphens help make numbers and fractions clearer.

✅ Correct: My little brother is two-thirds of my age.
✅ Correct: The test will have twenty-five questions.

👉 No hyphen needed for whole numbers like thirty or ninety-nine.

3. Hyphens in Prefixes (Sometimes!)

Hyphens aren’t always needed with prefixes, but they’re used when:

• The prefix is followed by a proper noun.
  ✅ Correct: She is studying pre-Columbian history.
• The same vowel appears twice in a row.
  ✅ Correct: He has re-entered the room.
• It avoids confusion.
  ✅ Correct: She is a small-business owner. (Not a "small business owner," which could mean the owner is small!)

👉 No hyphen needed for most common prefixes!
❌ Incorrect: Re-build the project.
✅ Correct: Rebuild the project.

Dashes: When to Use Them on the SAT

Now, let’s talk about the dash (—), which looks like a long hyphen but works differently. The SAT tests dashes a lot, so make sure you know when to use them!

1. Dashes for Extra Information (Like Parentheses!)

Dashes are great for inserting extra details into a sentence. They work like commas or parentheses, but they add more emphasis.

✅ Correct: My brother—who never studies—aced the SAT.
✅ Correct: The teacher gave us extra time—much to our relief.

👉 Rule: If you use one dash, it acts like a dramatic pause. If you use two dashes, treat them like parentheses.

2. Dashes for Sudden Breaks or Emphasis

Dashes can create a dramatic pause—something the SAT loves to test!

✅ Correct: I wanted to go to the party—but I had to study.
✅ Correct: There’s only one way to improve your score—practice!

Hyphen vs. Dash: How to Avoid SAT Traps!

Hyphens and dashes may look similar, but they serve completely different purposes—and the SAT loves to test whether you know the difference! A hyphen (-) connects words to form a single idea, while a dash (—) separates parts of a sentence for emphasis or interruption. Mixing them up can lead to awkward sentences and lost points, so let’s break it down:

📌 Hyphen (-) = Joins words in compound adjectives (e.g., a well-known author) and certain prefixes (e.g., ex-president).
📌 Dash (—) = Separates words or adds emphasis, replacing commas, parentheses, or colons (e.g., She finally arrived—two hours late!).

Final Thoughts

Mastering hyphens and dashes is a simple way to avoid easy mistakes on the SAT Writing & Language section. Just keep these key rules in mind:

✅ Use hyphens to connect words in compound adjectives, numbers, and certain prefixes.
✅ Use dashes to add extra information, create emphasis, or show interruptions.
❌ Don’t mix them up!

With a little practice, you’ll spot these punctuation marks like a pro. Now go ace that SAT! 🚀💪