Compound Adjectives with Numbers
Learn how to use hyphenated compound adjectives like 'a two-day trip' correctly.
- check_circleI can use hyphenated compound adjectives with numbers correctly.
- check_circleI understand why the noun inside the compound adjective is singular.
Discover
Meet today's English in a real situation — no rules yet. Read it once and try to guess the pattern in the words in bold. Underlined words open a short definition.
Anna: Hey, Mark! How was your vacation in London?
Mark: It was amazing, but exhausting! We had a ten-hour flight from Los Angeles, so we were pretty tired when we arrived.
Anna: Oh, wow. Did you manage to rest?
Mark: Eventually. We stayed at a beautiful four-star hotel near the city center. It was only a five-minute walk to the nearest subway station, which made getting around really easy.
Anna: That sounds convenient! Did you take any tours?
Mark: Yeah, we did a two-day tour of the historical sites. We even saw a five-hundred-year-old castle outside the city. It was fascinating.
Anna: I bet! Was it expensive?
Mark: A bit. I had to pay a twenty-pound fee just to enter the castle. But overall, it was totally worth it.
Learn
Now the rules behind what you just saw — explained simply, with examples. Underlined words open a short definition — hover on desktop, tap on a phone.
When we want to describe a noun using a number and another noun, we often combine them to form a compound adjective.
To do this, we join the number and the noun with a hyphen (-).
I took a two-week vacation.
The Golden Rule: Singular Nouns
The most important rule for these compound adjectives is that the noun inside the adjective is always singular, even if the number is plural. This is because adjectives in English don’t have a plural form.
Think of the compound adjective as one single word describing the noun that follows it. Since it acts as an adjective, it cannot be plural.
- Correct: We stayed in a five-star hotel.
- Incorrect: We stayed in a five-stars hotel.
Let’s look at some common examples:
- Time and duration: a ten-minute walk, a three-hour movie, a two-day trip
- Age: a five-year-old child
- Distance: a ten-mile run
- Money/Price: a fifty-dollar bill
- Weight/Measurements: a ten-pound bag
Spanish speakers often want to add an “-s” to make it plural (like “unas vacaciones de dos semanas”). Remember: No “-s” on the noun inside the hyphenated adjective!
I have a twenty-years-old car.→ I have a twenty-year-old car.
When NOT to use a hyphen
If the number and noun are NOT placed directly before another noun to describe it, we don’t use a hyphen, and the noun can be plural.
- Compound adjective: It is a ten-minute walk.
- Normal noun phrase: The walk takes ten minutes.
- Structure: Number + Hyphen + Singular Noun (e.g., ten-minute).
- Rule: The noun inside the compound adjective is NEVER plural (no “-s”).
- Usage: Place it directly before the noun it describes (e.g., a ten-minute walk).
- Difference: “A three-day trip” vs. “The trip was three days.”
Practice
Try it yourself. You'll see right away whether you got it right, plus a short explanation of why.
Use It
Now make the language yours in a real task. Use the prompt below — the editor keeps a simple word count, and nothing is saved or graded.
Before you finish — be honest. Can you do these now?