Numbers 0-20
Hook
Phone numbers, prices, ages, room numbers, bus numbers: numbers are in almost every real conversation. At A1 you need them fast and without thinking, so let’s learn 0–20, then the tens up to 100.
Notice
- 0 zero (or “oh” in phone numbers) · 1 one · 2 two · 3 three · 4 four · 5 five · 6 six · 7 seven · 8 eight · 9 nine · 10 ten
- 11 eleven · 12 twelve · 13 thirteen · 14 fourteen · 15 fifteen · 16 sixteen · 17 seventeen · 18 eighteen · 19 nineteen · 20 twenty
- 30 thirty · 40 forty · 50 fifty · 60 sixty · 70 seventy · 80 eighty · 90 ninety · 100 a hundred
- 21 twenty-one · 35 thirty-five · 99 ninety-nine
Look at 13–19. What do they all end with?
Rule
- 11 and 12 are special words: eleven, twelve.
- 13–19 end in -teen. Watch the spelling: thirteen, fifteen, eighteen (only one t).
- The tens end in -ty: twenty, thirty, forty (no u!), fifty.
- 21–99: ten + hyphen + number: twenty-one, forty-six.
- Stress: thirTEEN (13) but THIRty (30). The stress helps people hear the difference.
- Phone numbers: say each digit: 07 5 = “oh seven five”. Two the same = “double”: 55 = “double five”.
Watch Out
- ✗ fourty → ✓ forty (no u)
- ✗ fiveteen → ✓ fifteen
- ✗ I have 20 years. → ✓ I’m 20 (years old).
Practice
- Write the number: seventeen
- Write the word: 12
- Write the word: 40
- Write the word: 15
- 13 or 30? “She’s thirTEEN.”
- Write the word: 68
- How do you say the phone number 0772 559?
- What comes next? ten, twenty, thirty, ___
Show the answers
- 17
- twelve
- forty
- fifteen
- 13
- sixty-eight
- oh-seven-seven-two, five-five-nine (or: oh, double seven, two, double five, nine)
- forty
Your Turn
Say out loud: your age, your phone number (or an invented one), your house number and the number of people in your family. Then write them in words.
Connect
Our Spelling Quiz reads words aloud for you to type. It is a great way to fix tricky spellings like forty and eighteen.
Our Vocabulary lessons cover everyday words, including numbers.
CEFR A1 — Writing: I can write numbers and personal details on a form. Listening: I can understand numbers, prices and times when people speak slowly.
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