English · A1 · vocabulary · 4 minutes
Numbers 0–100
Use number building blocks for ages, prices, addresses, and phone numbers.
Understand the choice
English numbers keep tens before units: twenty-four. Practice the special spellings forty and fifty and use numbers with plural measurement nouns.
Core rule: Write compound numbers 21–99 with a hyphen between tens and units when the unit is not zero.
Notice it in context
The ticket costs twenty-four dollars.
El billete cuesta veinticuatro dólares.
Twenty-four has a hyphen and dollars is plural after a number greater than one.
My grandmother is seventy-one years old.
My grandmother has lived for 71 years.
Years old is the standard age frame.
The room is thirty dollars, and breakfast is forty.
The room costs 30 dollars and breakfast costs 40.
Thirty and forty appear as price amounts.
What to remember
- Forty has no u, although four has one.
- Hundred stays singular after a number: two hundred people.
Common trap: Do not reverse tens and units: twenty-four, not four-and-twenty in modern everyday English.