Compound Adjectives with Numbers

🟦What Are Adjectives?

Adjectives describe nouns. They come before a noun or after linking verbs like be, look, feel, etc.

✅ They have an expensive car.
✅ Your idea is fantastic.
✅ John looks tired.

🟩Compound Adjectives

Compound adjectives are made of two or more words joined by hyphens to act as a single adjective before a noun.

✅ a well-dressed man
✅ a part-time job
✅ a first-class ticket

🔗 Always use a hyphen to show the words work together as one idea.

🟦Number + Noun Compound Adjectives

We often use number + noun as a compound adjective before another noun—especially with units of measurement (mile, hour, dollar, kilogram, etc.).

✅ Correct Examples:

a 30-minute show
a two-day journey
a 50-metre pool
an eight-core processor
a two-bedroom apartment
a 10-million-dollar house
a seven-year-old child

❌ Common Mistakes:

❌ a ~~two-days journey~~ → ✅ a two-day journey
❌ a ~~30 minutes show~~ → ✅ a 30-minute show

🔑 Two key rules:
1. Use the singular form of the noun (even with plural numbers).
2. Always hyphenate the entire compound when it comes before the noun.

🌍 Note: metre, litre (UK) vs. meter, liter (US) — both are correct depending on dialect.

🟪Number + Body Part + -ed

When the noun in the compound is a body part, add -ed to form the adjective.

a three-legged table
a seven-headed dragon
a one-eyed alien
a four-armed robot

❗ Note: Double the final consonant if the body part ends in consonant + vowel + consonant and the stress is on the last syllable: leg → legged.

📌 Remember:
• Always use a singular noun in number compounds → “a 10-mile run” (NOT “10-miles”)
• Always hyphenate when the compound comes before the noun
• Add -ed for body parts → “a two-handed sword”
💡 These are fixed forms — learn them as whole units!