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Rule 2 of 6

Quick win

Thirteen versus thirty

The rule
Stress the end of -teen numbers and the start of -ty numbers.

In -teen numbers, stress the last syllable and hold its ii twice as long as a short i. In -ty numbers, stress the first syllable and say the final i short, with a full t.

This works the same way in both styles, and it prevents mistakes with prices, dates and quantities.

Stress in -teen and -ty numbers

The stressed syllable is louder, longer and higher. In -teen numbers it is the last one, and its ii is long.

13thəətiin
30thəəti
14footiin
40footi
15fiftiin
50fifti

-teen and -ty numbers

-teen-tyPlay both
13thirteenthəə-tiin30thirtythəə-ti
14fourteenfoo-tiin40fortyfoo-ti
15fifteenfif-tiin50fiftyfif-ti
16sixteensiks-tiin60sixtysiks-ti
17seventeense-vən-tiin70seventyse-vən-ti
18eighteenei-tiin80eightyei-ti
19nineteennain-tiin90ninetynain-ti

Twenty follows the -ty pattern: twen-ti, never twe-ni.

Listening to native speakers

Before a noun, native speakers sometimes move the stress forward ('thəə-tiin days'), so the long ii and the final n are your most reliable signal. Americans may say thirty as thər-di: listen for the long ii instead.

Confirm the number

For prices, dates, times and quantities, confirm the number in digits:

  • Thirteen, that's one-three.